Par Wars UK45 by Garden Culture Magazine

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CONTENTS

IMPROVING AIR CIRCULATION

FOR HEALTHY PLANTS

YOU, ME AND PHOTON EFFICACY

MARKETpLACE

PAR WARS LOCAL GROWERS

DIALLING YOUR GARDEN INTO THE 21ST CENTURY AND BEYOND

87 MY NEW ADDICTION: VINEGAR FERMENTATION

I N TH IS ISSU E O F GA R D EN C U LT U R E : 11 Foreword

13 Author SPOTLIGHT

66 Grow Room Ventilation 2.0 How LED Grow Lights Have Moved The Goal Posts

15 Marketplace

74 Mini Veggies, Big Yields

26 PAR WARS - Dialling Your Garden Into The 21st Century And Beyond

80 Green Manure: Optimise Your Soil This Year

32 Improving Air Circulation for Healthy Plants

87 Local Growers

38 The Solutions: Nature’s Monetary Value 44 Medwyn Williams Lights It Up for Award-Winning Harvests

90 Ventilation, Dehumidification And The Effect On Your Environment And Plants

48 Photosynthetic and other Photosensitive Pigments

96 LA Victory Gardens

100 5 Cool Ways

You, Me, and Photon Efficacy

56 My New Addiction:Vinegar Fermentation

84 Quenching The Thirst Of Food Crops With Dry Farming

102 Tissue Culture ll - Mushrooms

61 Takin’ A Bite Out of Labour - JAWS Soils

FOREWORD & CREDITS

FOREWORD

CREDITS SPECI A L TH A N KS TO: Adam Clarke, Albert Mondor, Anne Gibson, Av Singh, Betty Green, Brian Gandy, Dr. Callie Seaman, Catherine Sheriffs, Christopher Sloper, Evan Folds, Everest Fernandez, Jesse Singer, Martyna Krol, Nico Hill, Philip McIntosh, and Rich Hamilton.

t’s all in the title.The last five years in the hydroponic lighting industry have been quite the battle; LEDs have changed the game. Traditional lighting manufacturers were quick

to react, and due to a plethora of designs and eager Chinese manufacturers, the choices are many. Easy to make and buy but not always so easy to sell. There are several LED brands; I lost count at 50. Some markets around the world are still selling predominantly HPS, but they are fewer and fewer each year. As the prices of LEDs continue to fall and their efficiency continues to rise, it seems apparent that they will continue to gain in popularity.

What a great edition! Brian Gandy’s PAR WARS - Dialling Your Garden Into the 21st Century and Beyond humourously and scientifically explains the efficiency battle in our lighting market. Then, to push that discussion further, in the article You, Me, and Photon Efficacy, Christopher Sloper, the creator of the LED Grow Book, explains plant lighting efficacy down to the last photon. Growing under LEDs comes with its own set of challenges. If you have only used HPS and been successful, you will have to adjust. In Grow Room Ventilation 2.0 How LED Grow Lights Have Moved The Goal Posts, Everest Fernandez explains what you need to do differently to get the most out of your new lights. Award-winning HVAC expert Adam Clarke dives into how to control your grow room environment in Ventilation, Dehumidification, and The Effect On Your Environment And Plants. You

PRESIDENT Eric Coulombe eric@gardenculturemagazine.com +1-514-233-1539 E XECU T I V E ED I TO R Celia Sayers celia@gardenculturemagazine.com +1-514-754-1539 ED I TO R Catherine Sherriffs cat@gardenculturemagazine.com DESIGN Job Hugenholtz job@gardenculturemagazine.com D I G I TA L & SO CI A L M A R K E T I N G CO O R D I N ATO R Serena Sayers serena@gardenculturemagazine.com +1-514-754-0062 ADVERTISING ads@gardenculturemagazine.com PUBLISHER 325 Media INC 44 Hyde Rd., Mille-Isles QC, Canada J0R 1A0 GardenCultureMagazine.com ISSN 2562-3540 (Print) ISSN 2562-3559 (Online) Garden Culture is published six times a year, both in print and online.

can’t talk about lighting without considering your HVAC system and environmental control. We are thrilled to announce our newest writer Av Singh, PhD, PAg. An advocate of regenerative organic agriculture serving various organisations,

@GardenCulture

@GardenCultureMagazine

@Garden_Culture

including Regeneration Canada, Navdanya, and the Canadian Organic Growers, Av is one of Canada’s top organic consultants. In his first article, Takin’ A Bite Out of Labour - JAWS Soils, Av scratches the surface on how to switch to water-only soils. Happy Gardening,

Eric 3

D I ST R I B U T I O N PA R T N ER S • Maxigrow • One Love Inc • Nutriculture • Highlight Horticultur e

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, electrostatic, magnetic tape, mechanical, photocopying or otherwise, without prior permission in writing from 325 Media Inc.

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AUTHOR SPOTLIGHT

Every day is different. There are always pleasant surprises and things to troubleshoot.

Author Spotlight

Brian Gandy

ay hello to Brian Gandy, another Garden Culture contributor who really knows his stuff. We’re thrilled to feature Brian in our magazine; his

technical knowledge is sure to help us all become better growers. We know you’ll appreciate his PAR WARS ar ticle in this edition; before you dig in, get to know him a little better here! What’s your growing motto? Plants want to grow; this taught me to take a step back and observe more, provide what is needed and keep it simple. What do you love most about working in the growing industry? Every day is different. There are always pleasant surprises and things to troubleshoot. The headaches are rewarded by solving problems, and there is a deep satisfaction in that. And the people. Growers are a special breed. Misanthropic to some extent but almost always happy to talk shop and discuss techniques. Most won’t change their minds because we are a stubborn bunch but no matter where you are in the world, there is a common language in gardening. Do you grow Organic? I grow food mostly organic. The exception is indoors in the winter, when organic feeds can smell and be a little buggy. There is always an organic element, though. My hemp cultivation outdoors is always exclusively organic because it’s growing medicine. Sun Grown organic is the optimal choice when conditions are available. Indoor gardening, I lean toward synthetics for control and system optimisation. Depending on where your power comes from (coal, hydro, solar), there is an impact and obligation to get the most out of your garden. Overall, I believe in a hybrid approach still. Organics can do things for quality that full synthetics cannot achieve in my experience.

What is your favourite food? My favourite food comes from our garden or our local community. I’m a huge fan of all the nuances you get to taste when home gardening: broccoli leaves, cilantro pods, garlic scapes, squash blossoms, arugula flowers, bitter lettuce. Hemp is a staple in our family diet. We eat hemp hearts every day in smoothies and several other staple recipes. Hemp hearts have excellent protein and a perfect balance of Omega’s 3 and 6 for brain development. True brain food. Where in the world would you like to travel to next? Southeast Asia has always called to me. The tropics and sub-tropics, and mountain climates are all there and have unique plant and food experiences that I will take in as soon as possible. And Europe. The South of France has had a strong draw for the pastoral agriculture vibe that I’ve always read about. From there to the old-growth forests in Germany, then back down to the Mediterranean for Italy’s wine and arid abundance. 3

Are you interested in writing for Garden Culture Magazine? We’d love to hear from you! Send us an email introducing yourself with a sample of your work. editor@gardenculturemagazine.com

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Atami ATA NRG Flavour This bloom additive is based on beet molasses and is rich in potassium. Flavour encourages your plants to bloom while also developing strong stems. Used in the final two weeks of the flowering phase, Flavour stimulates sugar production, enhancing the flavour and aroma of your plants. As part of the ATA NRG range, this product is also suitable for environmentally conscious growers. Available in 1 litre and 5-litre bottles. Find out more: atami.com

Sun System RS1850 The leading American grow lights brand, Sun System® has arrived in Europe with the RS 1850 LED: an innovative 6 rail, plug & play foldable fixture with long life, high-efficiency diodes.This fixture is DLC listed, IP65 wet-rated and comes complete with a manual digital dimming button and an internal embedded smart controller compatible with the Gavita e-Series Controller. The fixture comes complete with a power cable and hanging wires for a quick and easy installation. This combined makes for a fixture that can be used in any size grow. Backed by a 5-year warranty and compatible with Gavita Master controllers. Visit SunSystemLights.eu to find out more.

Maxiswitch Quad Timer The saying “good things come in small packages” couldn’t be more appropriately used than for the allnew Maxiswitch Pro Quad timer from Maxigrow. It may look small and unassuming, but it sure is mighty in its performance. The 13 Amp unit can easily control up to 4 x 600W (or 2 x 1000W lights) from a single wall socket, freeing up precious socket space for other crucial grow-room equipment. Whether you are after a timer for one light or considering expanding your small hobby room, the Maxiswitch Pro Quad Timer has you covered. Head down to your local store or contact Maxigrow today.

Gro-Tank

by NutSystems Zero Media & Amazing Yields The Gro-Tank has been tried and trusted by growers for the past 45 years, delivering incredible results with zero media use. Plants sit on the Gro-Tank’s sloping tray while the nutrient solution is pumped from the tank over the bare roots on the tray above. The solution is continuously oxygenated with an air tube, and roots have unrestricted access to nutrients and oxygen, maximising nutrient uptake and growth. Plants are never underfed or over-watered, and there is no build-up of salts in the root zone. Proven results, healthier plants, and you can get more out of a small space Gro-Tanks are just 20cm tall. Visit Nutriculture.co.uk to learn more.

HELLION VARIABLE SPECTRUM III 10-BAR 8-BAR 6-BAR 4-BAR FOUR CUTTING-EDGE, HIGH INTENSITY LED FIXTURES BY ADJUST-A-WINGS

MULTI-DRIVER CONTROL & EFFICIENCY Adjustable spectrum and intensity across three channels (VEG, BLOOM, UV)

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Samsung LM301h 3k + 5k, Osram 660nm Red Osram 730nm Far-Red, Seoul 395 UV (all 50,000hr rated)

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Micro-reﬂector controlled light distribution for more intensity, deeper penetration and even coverage

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Ecothrive Manufactured in the UK, with all components sourced as locally as possible, Ecothrive offers natural, organic products centred around promoting beneficial soil biology, improving plant health and increasing yields. Both professional growers and hobby gardeners use Ecothrive products to build an assortment of microorganisms in the root zone. It’s all about providing long-term benefits and truly enhancing plant growth.

DAYLIGHT 480W LED

Follow @ecothrive for inspiration and tips on getting the most out of your garden. Available now from Highlight Horticulture.

The DAYLIGHT 480W LED 1104 µmol/s output fixture offers the same features and high-end quality of light found in its 660W bigger brother, but in a smaller unit that fits perfectly into a 1.2m x 1.2m area. This fixture is the perfect replacement for an existing 600W HPS lighting system. Don’t let the drop in power fool you. You can still gain a higher total output (PPF), meaning more useable light hitting your plants even with less power. Compared to a 600W HPS lighting system, the DAYLIGHT 480W LED produces a higher PPF of 1104 µmol/s vs 800-900 µmol/s. You’d be hard-pressed not to benefit from making the switch to LED! Visit GrowWithDaylight.co.uk for more great lighting solutions.

Plant Magic Magne-Cal+ Getting the correct ratio of Magnesium to Calcium right is critical for a successful grow. Magne-Cal+ does exactly that while also containing essential micronutrients such as Zinc, Copper, Manganese, Molybdenum, Iron and Boron. Magne-Cal+ prevents and treats deficiencies such as yellowing leaves whilst also boosting the efficacy of a phosphorus and potassium supplement, such as a PK booster, by balancing out the nutrient levels and providing the correct proportion of nutrients. It also regulates the transportation of nutrients while strengthening cells and supporting photosynthesis and enzyme processes. Trusted by growers for 15 years, MagneCal+ is known for consistent, exceptional results.

MegaPot An intelligent solution to enable growers to produce better results. Designed specifically with the hydroponic grower in mind, MEGAPot allows you to gain yields bigger than you’ve ever seen. The basic premise behind hydroponics is to allow the plant roots to get in direct contact with the nutrient solution while also giving access to oxygen, known to be essential for proper growth. The range includes the MEGAPot Module (16L, 22L, 39L, 56L), The MULTI POT, VEG POT with all parts. MegaPot also offers Fabric Pots to use with the systems. Check them out on Instagram: @megapotuk Available now at Highlight Horticulture.

TIP: Magne-Cal+ is also great for buffering reverse osmosis water and soft water by providing the plant with bioavailable nutrients. Find a retailer near you: Nutriculture.co.uk

T.A. GrowStream 2.0 Terra Aquatica is proud to present its new hydroponic system, GrowStream 2.0. It is based on the same technology as the Aeroflo (probably the most efficient hydroponic system on the market) but combined with several improvements, making it easier to use without compromising quality. Double walls in the tank, channel and lid for better UV barrier and insulation. More compact and stable with optimised dimensions for grow box. The size has been slightly increased compared to the AeroFlo to generate more root volume and water capacity, making it suitable for growing large plants. It is a versatile and modular system where you can choose to grow both large and small plants. Check out TerraAquatica.com to find more innovative systems.

Plant Magic Evolution 2.0 The Emergency Tonic That Gives Life To Your Plants! Every grower ought to have Evolution 2.0 on standby. It revives stressed plants, speeds-up vegetative growth and increases the development of new shoots. This unique 4-in-1 blend contains four natural products (catalyst, veg boost, bio wetter and wetting agent) from the Plant Magic range, all rolled into one easy-to-use formulation. Plants absorb the nutrients in a foliar spray more efficiently – so the results are faster than root feeding. Plus, Evolution 2.0 now contains an improved proprietary wetting agent, allowing you to spray with the lights on or off! Go to Nutriculture.co.uk to find a retailer near you.

DAYLIGHT 600W

CMH LAMPS Ever considered growing with full-spectrum CMH lamps but found the costs too prohibitive? With an improved, more robust design and built to work with 600W digital or magnetic power packs alike, the DAYLIGHT 600W 3K and 4K CMH lamps from Maxibright solve that problem for you. Both lamps provide full-spectrum light: 4K lamps are an ideal spectrum for the vegetative stage of plant growth, and the 3K lamps are suitable for the flowering stage or throughout the whole cycle. Easily integrated into any existing 600W lighting system, do your plants a favour and switch to ceramic metal halide lamps today. Contact Maxigrow for more details or visit GrowWithDaylight.co.uk

Green Sensation

A Powerful 4-In-1 Booster Improves flowering, resistance, soil, and yields without using a PK-fertiliser, enhancer, booster, or enzymes. Green Sensation helps develop stronger cell walls and more organic material. It contains active ingredients in the soil around your plant’s roots and ensures that the sap flow in the plant gets the proper nutrients. The powerful mixing ratio (1:1000) makes it very economical. There are no hormones, animal-derived residues, GMOs, or other substances that may have a harmful effect. Green Sensation produces the highest yield in every growing situation. Check out Plagron. com to find a stockist near you.

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SCAN TO LEARN ABOUT

AutoPot

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AirBase

120x240x200cm (4’x8’x6’6’’)

Give your plants a lift with AirBase. This handy plate fits into the bottom of your pot during set-up and allows you to sidestep the use of a pebble layer for drainage. Although simple, cheap, and practical, the preparation, pH balancing, and use of pebbles can be a chore. Instead, drop in AirBase and be on your way. This essential addition even features a pop-out centre-section allowing easy integration with AirDome (optional).

PRO White offers up to 106% MORE PAR reflectivity than Mylar with independent testing to back it up! Fully equipped with two main front doors, two side access doors, twelve port options in four sizes, two micro-mesh passive filters, and a one-night vision window. Strongly built using 25mm powder coated and tempered steel poles with metal push/click connectors.The tent also has roof hanging bars with silicone pads, main door clips, a clear floor area, double cuff vents, 20% oversized vents for acoustic ducting, and double-stitched seams. Award-winning grow tents. Grow PRO. Grow BudBox PRO.Visit BudBoxGrowTents.com to find the one that suits your needs.

AirBase Square will fit the 8.5L (2.2gal) and 15L (3.9gal) pots. The AirBase Round is designed for 25L (6.6gal) pots and 20L (5gal) fabric FlexiPots. A beautifully intuitive and effective innovation,AirBase is fabricated from rigid ABS plastic, making it highly durable and extensively reusable. Visit Autopot.co.uk to learn more about gravitypowered irrigation technology. TM

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Optic Foliar Optic Foliar manufactures high-quality foliar sprays that perform. Optic Foliar offers products that will deliver the foliar solution into the mesophyll layer, lights on, within 30 minutes with no damage or burning from residue or light burn. Cutting-edge and innovative foliar technologies, each product in the range work together as a highly efficient growth-promoting system for your plants. Plant leaves are the ‘factories’ where their food is created from carbon dioxide, water, sunlight or supplemental lighting, and chlorophyll. Water and nutrients travel from roots through the stem making their way to the leaves, the manufacturing facilities of the plants.The main objective of foliar sprays is to apply water and nutrients directly to the leaves, where they can be absorbed and used in the manufacturing process immediately. Available from Highlight Horticulture.Visit OpticFoliar.com for information.

Maxibright 600W HPS+ Dual Spectrum Lamps High-Pressure Sodium lamps remain the go-to lamp for indoor growers. Affordable, high-quality PAR outputs give consistent results crop after crop, like the Maxibright 600W Dual Spectrum HPS+ lamps, manufactured and developed by Maxibright. They have an immense total output of 1125 µmol/s that you will find hard to beat, and the unique Par-Lock feature means there will be no change in spectral output, regardless of how you choose to dim or overdrive the lamp! Visit your local store and treat your plants to the light they deserve with the Maxibright 600W Dual Spectrum HPS+ or contact Maxigrow for more details.

MARKET

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See what’s new in the growers MARKETPLACE

visit: GCmag.co/Product-Spotlight

BY BRIAN GANDY

Growers are making more informed decisions while still pushing the envelope of what should be possible.

PAR WARS

ong ago in a Trap House somewhere off

Anyone growing around

I-70, Legacy Growers, striking from hidden

the turn of the century

basements, were winning their first battles

knows the old standard

against the Evil Imperialist (Didactic?) Empire.

saber, the single-ended High-Pressure Sodium (HPS)

During one of these battles, Legacy Spies managed to steal secret plans to the Empire’s ultimate weapon, the REC STAR, a bureaucratic force with enough power to destroy an entire culture. Pursued by the Empire’s sinister agents, Princess Manna races home aboard the Mothership, custodian of the stolen plans that can save her people and restore healing to the masses.

New School Hope Anyone growing around the turn of the century knows the old standard saber, the single-ended High-Pressure Sodium (HPS). The weapon of choice was the 1000W in the US and the 600W abroad (more is better here in the States). All kinds of ducted hoods and reflectors to remove heat (hopefully in a discrete way that didn’t emit a thermal signature for the Empire to lock a tractor beam on) and distribute the light uniformly on the 2-dimensional plane that was your flowering canopy. This is how we achieved optimal yields in discrete, underground dens—layering the light from 1, 4, 12, or even 20 of these fixtures in a room as evenly as possible from these point source plasma bombs. All the old-timers remember the practice of “Super Cropping”, Low-Stress Training(LST), and other forms of canopy management that were the grow store lore in the early to mid-2000s. Basements have low ceilings; online forums had some low bars for actual science. This is, however, intuitively poignant when the conditions were what they were (and remain in many places). With only a few feet of clearance, it is essential to micro-manage every aspect of the growth of your plants to get the best and clearest path from your light source to your flower sites. Low efficiency, high heat, and limited contribution lighting justify this practice. To hit that magic benchmark of “1000 micromoles” of PPFD on your canopy, this was the way to do it. The theory is that the intentional stress to the plants elicits a positive response in the form of secondary metabolites. The reality is that you were just getting the most out of your limited fixtures. The net intensity from the lights (700-1000mmol) generates the potency, not the stress response. In ten years of commercial production, metabolite benchmarks have doubled, and few if any growers will go through a 100-light room to bend and caress

every plant into submission to get a “thank you sir” from the biological beauties under their synthetic stars. A quick search for the term “super cropping” still dredges up artifacts of Bro-Science that perpetuate to this day. This counterpoint to the term wasn’t true to me either until I saw my first room full of double-ended HPS, mounted 4 feet from the canopy of a room, turning out 2-3 pounds per light. Old basement rooms with manicured canopies would serve up 12 inches of baseball bats, and the rest was diminishing, whispy LARF to the bottom of the tropic zone. On top of that, the “canopy readings” of intensity were 750-850 mmol on average under these galaxies of high(er) efficiency HPS fixtures. How was this possible? Now, well-pruned (not pinched) and defoliated (per your Grower’s SOPs) rooms will deliver canopies of A-grade 30 inches or deeper. When double-ended fixtures started “falling off the back of trucks” on their way to commercial greenhouses and landing in warehouses of Legacy Forces, they realised the power of these fixtures was in larger arrays. The improved total output and efficiency turned into profits simply because of the light coming out of the fixtures. There was no longer a need to prune your garden like a boxwood. Let them grow tall and selectively prune the canopy of shading leaves at a few points of maturation, and the yields would improve without giving them PTSD.

Probing Photosynthetic Photon Flux Density PPFD, as it’s known now to so many gardeners, is the standard measurement of the amount of light measured “at canopy” level using a handheld meter like an Apogee sensor or the research standard Li-Cor 250A. The practice of indoor cultivation has evolved from gathering hydro shop pointers from your resident Wook selling the spider mite treatment du jour to the New School of Tyvek suits, Crop Steering, and SOP’s. We must modernise our understanding of lighting in the indoor garden.

PAR WARS

The private sector of Controlled Environmental Agriculture is setting new theoretical maximums for research on plant physiology. Growers are making more informed decisions while still pushing the envelope of what should be possible. They can now command up to and exceed 2000 micromoles of PPFD on canopy for sustained periods in artificial growing environments and see a return on the investment with yields above 120 grams per square foot of sellable product. This has been shown in tandem with some of the best Legacy Growers and Scientists on the task. Enabled by LED-based technology since the infrared heat from the old cutlass will no longer physically fry the plants underneath the dialled, diode-based transmission of refined PAR. We are looking more at DLI (Daily Light Integral) and agronomic terms rather than the limited metrics imposed by the old Death Stars. This has been achieved by several arm-ripping hippies of the Legacy Force who could not be told “NO”. Seeing is believing, and these furry savants are doing what, until recently, could not be done.

Most of the terminology used to define lighting for indoor gardens is extrapolated from “visual” perception by people, i.e. Inverse Square Law, lux, and lumens(are for humans). If you light a candle and walk incremental distances away from it, the candle will get dimmer and dimmer (albeit visible from a very long way away). But this doesn’t mean the candle is putting out any less light; it is just a measurement of how our eyes and brains quantify the light. Humans and plants perceive an uncanny evo-

We must modernise our understanding of lighting in the indoor garden.

lutionary slice of the electromagnetic spectrum (400-700nm), with human perception peaking around 535nm, aka green. This is how lighting design software like DiaLux and AGI 32 can adapt to horticultural layouts through some keen conversion factors. This is a limited interpretation. Layouts and design are still an integral part of approximation, even if they are based on a quantitative parallel. PPFD, like lux levels, can be manipulated on a 2-dimensional surface using optics. But we know from the old online, multi-coloured LEDs that touted “200 watts can replace a 1000W HPS” that 3000 mmol from a PAR meter did not equate to an equal yield from these old bastards of the early marketed technology.

We are dealing with a 3-dimensional canopy matrix and must use a Systems Engineering approach. If you have a shotgun with a birdshot choke or a sawed-off and shoot each at the side of the barn from five paces away, one will blow a tight patterned hole, and the other will scatter the shot. It doesn’t change the amount of energy or lead shot in the shell. The rate of output is the same. This is known as Photosynthetic Photon Flux in horticultural lighting. Take the

LET’S GROW ©2020 - MAMMOTH IS A COLORADO BASED COMPANY THAT DEVELOPS SCIENTIFICALLY DRIVEN SOLUTIONS TO MAXIMIZE CROP PRODUCTIVITY. MAMMOTH® IS A BRAND OF GROWCENTIA, INC / FOR MORE INFORMATION MAMMOTHMICROBES.COM

PAR WARS

There is a cult of truth-seekers not falling for the mind tricks.

Recent battles have begun, and cancel culture is alive and well in the indoor Horticulture market where BS is being called to the public for brands peddling their modified truths

wattage(650) and multiply by the efficacy in mmol/Joule(2.7), and you’ll get the total rate of Photosynthetically Active Radiation emitted by this fixture (1755mmol). The total rate of inputs correlates to the successful realisation of sellable units from any garden. DE fixtures upped the game with efficiencies at or above 2.0 mmol/J, while SE lamps were capped at around 1.6 at best. That is the difference of 2100 usable photons versus 1680; 20% more light from the same wattage. LEDs now surpass 2.7 mmol/J for “white” or broad-spectrum and more than 3.4 for “blurple” or targeted Red: Blue spectra. Without the heat.

The Battle of Las Vegas Visit any of the large industry shows now, and you will find a melting pot of Legacy Growers and Capitalists like nowhere else in the Universe. Wooks and Wingtips commingle in a cabalistic, social media-induced cesspool. Many Growers have transitioned from forums to their feeds for information. The hype of overstated claims, flagrant false advertising, memes, social commentary, and subliminal marketing is producing some unintended and just results. While it is the new pipeline for information and can be full of horse shit every day, some internet sleuths and budding scientists are making their marks. Recent battles have begun, and cancel culture is alive and well in the indoor Horticulture market where BS is being called to the public for brands peddling their modified truths.

There is a cult of truth-seekers not falling for the mind tricks. Some tenured scientists and fresh Master’s candidates are out there providing and accepting feedback in live time. Peer-Reviewed Journals are now publishing on our favourite crops, and the masses have spoken loud enough to force companies to clean up their acts. This transdisciplinary and integrative approach to information intake is essential to getting your garden dialled into the 21st century and beyond.

Spaghetti Western of Science The battle for Truth rages on and the feedback cycle from the Dark Side to the Light is in motion. Technology initially funded by NASA has been applied to counter-culture crops, and now science is picking up the pieces of innovation, driven by this unparalleled boom. Any chronicle is in a constant state of flux and the horticultural story is brimming with paradigm-shifting potential.

BIO Brian Gandy is the founder of Sustainable Terrains

and a Horticulturist with over a decade in applied cultivation technology from Organic Field Crop Production to Controlled Environmental Agriculture.

BY ANNE GIBSON

p Im

g n i v o r

t a i l o u n c iC r thy Plant l a e s H r fo

n nature, outdoor plants tend to grow strong and healthy, with the wind helping to strengthen stems as they grow. However, in our gardens – indoors and out – we often inadver tently

create problems by not addressing adequate air circulation.

Gentle winds help reduce humidity levels and improve plant health by reducing environmental conditions favourable to common diseases

IMPROVING AIR CIRCULATION

Citrus trees with poor air circulation may get inadequate light grow weak and attract pest problems

Powdery mildew is a common problem that can be avoided by improving airflow and controlling humidity

Why is airflow necessary? Circulating air impacts CO2 levels, humidity, and a plant’s ability to take up nutrients. Natural breezes blow air onto seedlings and branches, helping fortify the cell walls as plants grow. Gentle winds help reduce humidity levels and improve plant health by reducing environmental conditions favourable to common diseases. Soil aeration also promotes healthy root growth.

What problems can we avoid? Fungal diseases: Humid, still air around plants can create an environment conducive to common plant diseases, including powdery mildew and blackspot. Mould spores thrive in moist conditions, particularly in warmer months, and these can quickly spread to neighbouring plants. Where tree canopies are closed and overcrowded, branches and leaves struggle to access adequate ventilation and sunlight. This not only limits growth potential and yields but encourages fungal diseases. They are more likely to spread across the tree than affect just a section. Consistent air movement helps minimise the potential for these problems. Pests: Damp soil with insufficient surface aeration can attract fungus gnats, spider mites, slugs, and snails. With suitable moist, humid habitats, these pests can cause significant plant damage. Breezes can also help deter flying insects like mosquitos and fungus gnats by disturbing stagnant air spaces. Poor pollination: High humidity and temperatures can affect successful pollination. Pollen may clump together, and some plants will not release pollen at high temperatures. Good airflow, however, helps regulate temperatures and moisture levels so pollination can take place. In overcrowded growing conditions, pollinators may struggle to access flowers, so pruning and plant spacing are vital techniques to implement.

How can we improve ventilation around our plants? Outdoors Firstly, a row of shrubs or trees is often intentionally planted as a protective windbreak or privacy screen. However, it’s essential to consider spacing plants to allow air movement between or around them in garden beds. This is particularly important for edibles susceptible to diseases exacerbated by humidity and inadequate sunlight. For example, the cucurbit family includes pumpkins, zucchini, and cucumbers that suffer from powdery mildew. However, careful plant choice and location can create favourable microclimates for sun, shade, and protection without negatively impacting airflow. Secondly, assess any hedges, windbreaks, walls, or solid structures that may hinder breezes and obstruct natural light where it is needed. Allow adequate space between these design elements and your plants. A notable exception is shade-loving plants that thrive in a moist environment with multiple canopies and tiered cover from taller species. Many shade-tolerant species are generally not as susceptible to fungal diseases as they have adapted to this habitat.

it’s essential to consider spacing plants to allow air movement between or around them in garden beds

GA R D EN CU LT U R E M AGA Z I N E.CO M

stagnant air with high humidity can reduce CO2 availability, so it’s essential for adequate ventilation and fresh air Poor pollination on corn cob as a result of inadequate airflow and wind

Thirdly, if your garden is in a low set location, perhaps susceptible to fog or damp, stagnant shaded areas, try vertical garden structures, terracing, or planting on swales to improve air circulation. Pruning taller species by opening up tree canopies can also enhance airflow. For example, citrus trees often have excessive new growth in spring. They benefit from shaping and selective pruning internally to avoid branches crossing over and causing damage. We can snip off new growth tips before the tree puts its energy into stems that are growing in the wrong

direction. I regularly prune my citrus when dormant over winter to improve air movement in the tree’s centre and as it matures. This not only helps prevent diseases but enhances yields and access for harvesting. Fourthly, crop protection is necessary for many climates where protection from heat and intense sunlight is crucial for plants to survive. I tend to use permeable shade cloth covers that allow light, airflow, and rain in but protect against damaging winds, heavy rain or hail storms, and pests. Breathable covers allow air to circulate freely while still providing other benefits. Finally, seed packets and plant labels usually provide an accurate guide to spacing to help you allow adequate room when plants mature.

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IMPROVING AIR CIRCULATION

Vulnerable crops can be protected with suitable shade cloth that allows adequate ventilation while providing other benefits

The bottom line is to ventilate indoors Indoors Plants grown inside a greenhouse or our homes and offices also need good ventilation. Plants release moisture through stomata, the small pores in their leaves, via transpiration. Water vapour moves from the open stomata into the surrounding air, increasing humidity. CO2 and oxygen move in and out of the plants through photosynthesis. These functions are vital for healthy plant growth. However, stagnant air with high humidity can reduce CO2 availability, so it’s essential for adequate ventilation and fresh air. In addition, dust and pollen can accumulate on houseplant leaves, affecting their ability to function efficiently. Fixing this may be as simple as opening doors and windows to encourage air movement at no cost or turning on a fan if there are no cross breezes. Condensation and mould on indoor windows and surfaces can also result from inadequate airflow, affecting human health and plants. Results from a CFD study(1) on improving airflow uniformity in indoor plant factory systems showed that “enhancing the wind velocity has a positive effect on photosynthesis and transpiration.” This study indicated healthy growth is improved with better air circulation, particularly for plants grown indoors. As hot air is drawn upwards through roof ventilation in greenhouses, it is exchanged for cooler air, helping regulate internal temperature and maintain CO2 and humidity levels. The bottom line is to ventilate indoors.

Container Gardens Another aspect of airflow that needs to be considered relates to potted plants. Some pots are manufactured from porous materials, including unfired clay or terracotta, wood, coconut coir fibre, and paper pulp. These containers ‘breathe’ and permit water and air to permeate more easily. However, there are pros and cons to consider! Pros: Air circulates more easily around the root zone, making oxygen available to plants for healthy growth. As water wicks through the permeable material to the outside of the pot, the soil cools. Extra moisture can escape, and this helps deter root rot problems. Drainage is improved when potting mix ingredients like vermiculite, coarse sand, or perlite are used. These materials increase the air pockets within the mix, encouraging healthy root growth.

Condensation and mould on indoor windows and surfaces can also result from inadequate airflow, affecting human health and plants

GA R D EN CU LT U R E M AGA Z I N E.CO M

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IMPROVING AIR CIRCULATION

Another way to improve airflow around your pots is to get them up off the ground if they Unfired clay porous pots are best suited to succulents and hardy plants

Cons: Unfortunately, while porous pots offer good aeration properties, the potting mix tends to dry out faster. In full sun locations, excessive moisture loss can cause plant stress and require more frequent watering! It may be wise to match your pots to plants in these circumstances. Porous pots may better suit plants that benefit from drier soils with good aeration, such as succulents and perennial herbs. Another way to improve airflow around your pots is to get them up off the ground if they sit in saucers. Vertical structures, plant stands, and pot feet aid aeration and prevent stagnant water from accumulating around the pot’s base. Self-watering containers also improve soil aeration and drainage. By applying some of these suggestions, we can design our indoor and outdoor gardens to benefit from improved airflow and minimise problems. 3

sit in saucers

Vertical structures, plant stands, and pot feet aid aeration and prevent stagnant water from accumulating around the pot’s base.

References: (1) A CFD study on improving airflow uniformity in indoor plant factory system - Biosystems Engineering, Volume 147, 2016, Pages 193-205

BIO

Anne Gibson, The Micro Gardener, is an author, speaker and urban garden community educator on the Sunshine Coast, in Queensland, Australia. Anne is passionate about inspiring people to improve health and wellbeing, by growing nutrient-dense food gardens in creative containers and small spaces. Anne regularly presents workshops, speaks at sustainable living events, coaches private clients and teaches community education classes about organic gardening and ways to live sustainably. She has authored several eBooks and gardening guides. Anne shares organic gardening tips and tutorials to save time, money and energy on her popular website - TheMicroGardener.com.

GA R D EN CU LT U R E M AGA Z I N E.CO M

BY EVAN FOLDS

The Solutions:

Nature’s Monetary

Value “Though the problems of the world are increasingly complex, the solutions remain embarrassingly simple.” - Bill Mollison, the “Father of Permaculture.”

NATURE’S MONETARY VALUE

How can we sit around the table and identify the big challenges that we collectively face and even many of the solutions, yet the problems seem to worsen?

ome attribute this riddle to a crisis of compromise—others, to an invisible hand controlling society. But regardless of the reason, we cannot wrangle our problems. One thing is clear: our current economy is ruining the ecosystem of the Earth and is built to concentrate wealth and not serve the average person. The top 1%

holds 42.5% of all national wealth; no other country in the world has so much in the hands of so few.

Benito Mussolini once said, “Fascism should more properly be called corporatism since it is the merger of state and corporate power.” Until we address corporate power and the corporatism alive within federal and state governments, we will be stuck powerless in the vicious cycle that has brought us to the brink of socio-economic disaster. As they say, the first step is identifying the problem.

What if, instead of deciding Nature has no value, we decided to build economic systems that recognised the value of living systems?

The Systems At Work But the discussion cannot just be about dictators and evil rich moguls. Let’s not make it personal; there is nothing wrong with being wealthy, and people are inherently good. Rather than focus on the people, we need to be focused on the systems. For instance, 40% of food goes to waste. Yet, the WHO estimates that roughly a tenth of the global population – up to 811 million people – were undernourished in 2020. In a world of compassionate human beings, how can this be? The primary reason for this enigma is that it is not profitable to preserve the wasted food and deliver it to those in need. This is not cynical; we cannot escape our economy in the world we have built. Money talks. If it is profitable, someone will sign up to perform the service. This suggests that, rather than expecting things to work as they should, the transformational work of our time will use the economy to develop stories and incentives that bring about the desired result. Consider the concept of true cost accounting. Typical accounting within a company does not include natural and social capital impacts. For example, a factory that pollutes the environment creates a cost to society, but those costs

are not priced into the final good that it produces. The economic theory calls these hidden costs “externalities” or a consequence of an industrial or commercial activity that impacts other parties without it being reflected in the cost of the goods or services involved. In other words, if Mother Nature has no value, how does she hit the balance sheet?

Nature’s Value It is important to recognise that our current socio-economic systems are not broken; they are deficient and can be fixed. As Bucky Fuller reminds us, “You never change things by fighting the existing reality. To change something, build a new model that makes the existing model obsolete.” What if, instead of deciding Nature has no value, we decided to build economic systems that recognised the value of living systems? The legal landscape of the United States has been built on 150 years of precedent in support of corporate personhood at the expense of individual human rights and the undeniable value of the services provided by Nature. This precedent is being used to secure corporate power at the expense of the average person, which explains why we can all understand the problems and nothing ever changes. The question becomes, what are we going to do about it? The way forward is not in judgment, finger-pointing, or party politics but in recognising that the world is written by narrative and incentive. If we get the story right, and we can toggle the economic incentives towards regenerative methods, we can fix corporatism and inspire the people of the Earth to move the mountains in front of us in the world.

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NATURE’S MONETARY VALUE

Whales play a significant role in capturing carbon from the atmosphere

Plans With Potential The foundations for a New Earth are already being championed and developed. I have written about regenerative agriculture and its capacity to engage the significant challenges that we face. I have also written about the Rights of Nature and the potential that this legal strategy has to bring balance to justice from the perspective of people and life, not just profit.

The manure of whales contributes to phytoplankton blooms that not only contribute at least 50% of all oxygen to our atmosphere but capture about 37 billion metric tons of CO2 annually, an estimated 40% of all CO2 currently produced

There is a parallel effort to valuate natural capital underway, being led by Dr Ralph Chami, an economist with the International Monetary Fund (IMF) who is now on a mission to shift the consciousness of economic theory to help save us from ourselves. Four years ago, on a trip to observe the Blue Whales in the Sea of Cortez, he met a team of scientists who first introduced him to the ecosystem services of whales, and he is now telling a story that has the potential to bring abundance back to the Earth.

A Whale’s Worth Whales play a significant role in capturing carbon from the atmosphere. They accumulate carbon in their bodies during their long lives, and when they die, they sink to the bottom of the ocean, taking, on average, 33 tons of CO2 with them, removing it from the atmosphere for centuries. For perspective, a tree absorbs only up to 48 pounds of CO2 a year.

Whales play a role in the ocean, similar to ruminants on land. The manure of whales contributes to phytoplankton blooms that not only contribute at least 50% of all oxygen to our atmosphere but capture about 37 billion metric tons of CO2 annually, an estimated 40% of all CO2 currently produced.

When protected, these stores of carbon can be certified on the open market for organisations such as corporations or local governments to purchase to offset the carbon that they produce. This allows organisations to operate in a carbon-neutral capacity, and it provides a healthy incentive for capital to be used towards the conservation of living systems. Win-win. Once Dr Chami understood this value from a market perspective, with his deep background in finance, he quickly got to work doing the calculations, and what he came up with is incredible. The value of the current ecosystem services provided by each one of the great whales was a minimum of $2 million. The calculation is not the value of the whale; one could argue that this is priceless. Instead, it is the value of the current services the whale is providing. For instance, whale watching is a $2 billion industry; why would this value not be recognised in the whale’s life?

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NATURE’S MONETARY VALUE

The calculation is not the value of the whale; one could argue that this is priceless. Instead, it is the value of the current services the whale is providing.

Carbon Sequestration Carbon sequestration is a burgeoning market. Several years ago, carbon markets were only an idea. The current market value for carbon is up to $100/ ton. Bloomberg estimates the value per ton could increase 50-fold by 2050, so this market incentive will only get stronger.

It is revolutionary and paradigm-shifting, and while that is never simple, it represents a real opportunity to radically change humanity’s impact on the living systems that sustain us

The repercussions of this work are extraordinary. Consider that in our current economy, a whale is worth nothing. A whale is only worth something when it is dead, which amounts to anywhere from $40,000-$80,000 for its body parts. So the way to save the whales is not by protesting whale hunting fleets but by assigning value to the whales’ services; could it be that simple? Yes. For instance, there is no penalty for a boat hitting a whale. But as soon as that whale has a certified value of $2 million, that all changes. Not only does this disincentive illegal whaling, but insurance companies then have to rethink their stance. Sea lanes will change to go around whale grounds, which helps

to heal the Earth and move us towards a more sustainable posture for the human species.

Revolutionary Solutions

Now, take this principle and project it out into the greater expanse of Mother Nature. Dr Chami has calculated the ecosystem services of forest elephants and found that each elephant is worth $1.75 million for the services that it provides. His team estimated that the seagrasses in England are worth $4.2 billion in carbon sequestration and flood control. The possibilities are endless. This work is only beginning, but it provides a bridge to a brave new world. It is revolutionary and paradigm-shifting, and while that is never simple, it represents a real opportunity to radically change humanity’s impact on the living systems that sustain us. Our challenge is the potential to solve the problems that we face. Our challenge is in changing the habits of a materialistic culture driven by a profit-at-all costs economy. Game on. 3

Bio

Evan Folds is a regenerative agricultural consultant with a background across every facet of the farming and gardening spectrum. He has founded and operated many businesses over the years - including a retail hydroponics store he operated for over 14 years, a wholesale company that formulated beyond organic products and vortex-style compost tea brewers, an organic lawn care company, and a commercial organic wheatgrass growing operation. He now works as a consultant in his new project Be Agriculture where he helps new and seasoned growers take their agronomy to the next level.What we think, we grow! Contact Evan at www.BeAgriculture.com or on Facebook and Instagram @beagriculture

BY NICO HILL

Medwyn Williams Lights It Up For

¨We started out using T5 fluorescent-type lighting on seedlings, and probably around the same time, began using metal halide and HPS lighting for supplementing natural daylight in our greenhouse,” Medwyn says. “Getting the best quality light in the run to show deadlines can be hard, so making sure endless cloudy days don´t get in the way plays a huge part in us being able to grow the best quality veg on time.”

Award-Winning Harvests

hen it comes to growing the highest quality show-winning vegetables, there arguably isn´t a finer champion than

Medwyn Williams of Anglesey. Medwyn is a 13-time Chelsea Gold winner and owner of countless other gardening accolades! Growing in the UK, he integrates a variety of Maxibright lighting fixtures to get the best harvest out of his greenhouses.

Supplementing natural daylight on cloudy days is a long-standing practice in greenhouse horticulture. Of course, nothing quite beats the reliability and affordability of tried-and-tested lighting like HPS and Metal Halide, but they do have newer contenders on the block. Keen to keep on top of his gardening game, Medwyn is no stranger to the more recent Ceramic Metal Halide and LED fixtures. He decided to take advantage of these lights after a carrot crop went wrong during the first year of the COVID-19 pandemic. The Chelsea Flower Show date changed, switching up an entire year’s planting times and forcing Medwyn to approach things slightly differently.

Display stand at Malvern

AWARD-WINNING VEGETABLES

“Timing of crops is very important to us because of having to display everything on the Chelsea stand all at the same time in the very best condition possible,” he says. “Now, of course, we had to replant everything and display completely out of the usual season.” Medwyn needed to find a lighting solution for his prize-winning carrot variety that not only gave an excellent and intense uniformity but offered a full spectrum of PAR lighting due to the absence of the required sunlight levels.

Supplementing natural daylight on cloudy days is a longstanding practice in greenhouse horticulture

Small and large LEDs

To control the environment, they set up a large Budbox grow tent inside their polytunnel and used a combination of the red and blue 315w DAYLIGHT horizon lights. The plants responded well; the full spectrum offered even light coverage over the entire crop, and the carrots ended up being perfect.

normally consider with the seeds being under the soil surface.” He further eluded to research they are doing with universities in a very mysterious and hush-hush way; time will tell where using new technology will take him and his plants in the future. “Plant lighting is a fascinating and complex subject, so being able to rely on Maxibright and DAYLIGHT products means we can rely on our plants to win shows, but ultimately, just grow to the best of their ability.”

¨The carrots were some of the best we have ever grown, and the heat from the lights kept the rest of the polytunnel warm, which helped some of the other plants too,” he says. “Then, of course, the re-scheduled Chelsea Flower show was also cancelled, so we ended up just eating them all – they were delicious!” More recently, Medwyn has added LEDs to his lighting toolbox and has enjoyed incredible results, noticing faster root development and better quality plants. ¨We´ve even had some surprising results with simply germinating our onion seeds underneath [the lights], he explains. “It sounds unbelievable, but underneath the 660W daylight, germination times were massively improved. Not something you´d

For more information on what Medwyn is up to, visit medwynsofanglesey.co.uk. 3

GET ILLU Maxibright ‘Special Chemistry’ 600W HPS & MH Lamps

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BY DR CALLIE SEAMAN

Photosynthetic and

Other

Photosensitive

Pigments

The most well-known pigment is chlorophyll, but let’s have a look at phytochrome, how they react to light, their function, and their location.

lants are incredible organisms that capture carbon dioxide (CO2), turning it into carbohydrates and beautiful fruit and flowers. However, they cannot do this without the help of water and the

tiny packages of light called photons. These elements feed into the process known as photosynthesis.

PHOTOSENSITIVE PIGMENTS

Phycobilins Photosynthesis requires unique organelles Strictly speaking, there Phycobilins are another type of accessocalled plastids, which are found in plants are only three types of ry pigment. However, they can bind to and produce food or pigment. Plastids are an entity of their own and are technically photosynthetic pigments: water-soluble proteins to form Phycobiliproteins, which pass the energy they considered intracellular endosymbiotic cyachlorophyll, carotenoids capture from light to chlorophylls for nobacteria. They are believed to descend photosynthesis. This has only been found from bacteria, forming a mutually beneficial and phycobilin in a red variety of algae. relationship with algae close to the start of life. We are probably most familiar with chloroplasts, which are found in chlorophyll and perform photoPhytochromes synthesis, but others include leucoplasts and chromoplasts. Plants do not germinate with chlorophyll in them. Therefore, they rely on the food stores of the seed until it reaches the light This article will focus on photosynthetic and photosensitive pigand the construction of the chlorophyll and the other photosynments, which require light as stimuli. This reaction to light is not thesis apparatus can start. There are five types of phytochrome limited to activating a process or photosynthesis; some pigments named A to E. These are photochromic pigments, meaning they turn off gene expression, and some trigger and control germinacan change colour when absorbing specific wavelengths of light. tion. Others dictate the type of growth and circadian rhythm of the plant. They can even help the plant avoid the shade! Phytochromes have two forms, often referred to as Pr and Pfr. When the Pr form is exposed to red light within the visible spectrum, it converts to Pfr. Pfr, on the other hand, absorbs light on Chlorophyll the far-red end of the spectrum. Therefore, the ratio of red to Strictly speaking, there are only three types of photosynthetfar-red light is essential in the development of plants, as this does ic pigments: chlorophyll, carotenoids and phycobilin. These are not only control germination but other processes such as the pigments that undergo photosynthesis. You are probably familshade avoidance response, etiolation of seedlings, gene expresiar with chlorophyll, the substance that makes leaves green and is sion, and circadian rhythm (the internal 24-hour clock). where photosynthesis occurs. But did you realise that chlorophyll includes a group of photosynthetic pigments? The table below lists When Phytochrome A is exposed to light, it rapidly degrades, the array of different chlorophyll and the wavelength of light they which is why it is predominantly found in the very early germiabsorb. There are the plastids within the chlorophyll that are chlonation phase. This degradation leads to the other phytochromes roplasts; this is where all the magic happens. (B-E) increasing and taking over the interruption of light signals and fully functional photosynthetic equipment development. Carotenoids

On the other hand, carotenoids tend to be more on the red end of the spectrum, from the bright red lycopene to the more orange carotene. Some yellow carotenoids give tomatoes, pumpkins, carrots, daffodils, lobster, and autumn leaves their colour. They are also responsible for the colour of spider mites and aphids. Carotenoids are photosynthetic compounds. However, they are classified as accessory pigments. They will often bind to chloroplasts within the dominant type of chlorophyll, Chlorophyll A, and increase the range of wavelength of light that can be absorbed and turned into carbohydrates. Chlorophyll A can only absorb 400–450 nm and 650–700 nm. Carotenoids, such as carotenes, absorb 450-480nm and xanthophylls 400–530 nm.

Flavoproteins Finally, let’s look at a type of photoreceptor protein known as flavoproteins. These pigments allow the plant growth to respond to its environment. Flavoproteins absorb light at the blue end of the spectrum (450- 495nm) and are responsible for processes such as phototropism (moving towards the light).

We are probably most familiar with chloroplasts, which are found in chlorophyll and perform photosynthesis, but others include leucoplasts and chromoplasts

PHOTO SENSITIVE PIGMENTS

Some yellow carotenoids give tomatoes, pumpkins, carrots, daffodils, lobster, and autumn leaves their colour One of the most well-known flavoproteins is probably phototropin, which is directly involved in the movement of the stems towards the light. They also help with the opening of stomata and the movement of chloroplasts. Another flavoprotein is crypto-

chrome, which has photosensitive properties. Cryptochrome is responsible for circadian rhythm within the plant to sense day and night. It is also interestingly involved in sensing magnetic fields and gravity. 3

The different types of Photosynthetic Pigments are shown in the table below. Photosynthetic Type Molecular structure Colour Absorption spectrum Distribution Pigments (nm) and notes Chlorophyll-a

Chlorophyll

blue-green

Chlorophyll-b

Chlorophyll

yellow-green

Chlorophyll-c

Chlorophyll

blue-green

400–450 nm 650–700 nm

All photosynthetic plants except bacteria. Dominant form found in plants.

450–500 nm Higher plants and green algae. 600–650 nm Accessory pigment that helps to broaden the spectrum. 447-452nm

Seen in Diatoms and brown algae.

Chlorophyll-d Chlorophyll red 710 nm Found in some red algae and in deep water species when light is very limited.

Carotenes carotenoids orange/red 450–480nm Found in algae and higher plants, carrots, red peppers, mango. Xanthophyll

carotenoids

yellow

400–530 nm

In algae and higher plants.

Lycopene carotenoid red 440-505nm Peak at 444nm, 471nm, 503nm

Seen in fruits and vegetables such as tomatoes. Not strawberries or cherries.

Phycoerythrobilin

Phycobilin

red

545nm, 572nm

In blue green algae and red algae.

Phycocyanobilin

Phycobilin

blue

610 to 660 nm

In blue green algae and red algae.

BIO Dr Callie Seaman is a leading expert of the UK hydroponic industry and became passionate about medicinal cannabis when she was diagnosed with epilepsy over 20 years ago.After obtaining a Biomedical Sciences degree at Sheffield Hallam University, she completed a PhD titled “Investigating Nutrient Solutions for Hydroponic Growth

of Plants”. During her PhD, she became a founding director of Aqua Labouratories Ltd – a formulator and producer of specialist hydroponic nutrients. In October 2018, Callie became a non-executive director of a home office licenced medicinal cannabis facility within the UK. She consults with a wide range of other licensed producers worldwide as they look to set up their facilities.With numerous scientific articles, book chapters and peer-reviewed papers to her name, Callie is an experienced professional in the field of medicinal cannabis, cultivation and fertiliser science. @dr.callieseaman

@DrCallieSeaman

@dr_CallieSeaman

linkedin.com/in/dr-callieseaman Web: aqualabs-uk.com & cbdhempire.co.uk

Pioneering References

m a m a p u b li s h i n g. co m

BY CHRISTOPHER SLOPER

You, Me, and

Photon Efficacy

PHOTON EFFICACY

he term photon efficacy has been getting much attention lately, but do you know what it means? It’s a measurement of how many individual packets of light (called photons) are generated by a single watt of electricity; this is one of several performance metrics to consider when selecting a grow light.

Calculating photon efficacy is straightforward. You divide the fixture’s total light output (µmol/s) by the actual watts (J/s) used. Total Light Output ÷ Total Watts Used = Photon Efficacy For example, let’s say you have a grow light that produces 2000 µmol/s of light energy and uses 800 watts in the process:

When I grabbed onto one of the bars on the light, it all became clear. With higher photon ef ficacy, this new light produced more light and less heat than its predecessor

2000 µmol/s ÷ 800 J/s = 2.5 µmol/J Measuring the total light output from a grow light requires specialised equipment called an integrating sphere. As the name implies, an integrating sphere is round in shape, and its job is to “count” the individual photons. However, they are costly and require trained personnel to operate them. I learned something interesting about integrating sphere testing on a recent project. The manufacturer’s representative that I worked with won’t test fixtures more than twice (think two different voltages) in an integrating sphere as things start to change. Unfortunately, I did not have the chance to dig into his reasoning as my friend suddenly passed away (R.I.P. Jay; I miss you).

If the manufacturer can’t per form this simple calculation accurately, you should not purchase the light from them

LED Golden Samples

A “golden sample” is a fixture designed to be sent to a lab to achieve incredible results from testing but not be used for actual cultivation. Golden sample fixtures typically contain expensive, ultra top-end LEDs, making them cost-prohibitive for general distribution. Or, the manufacturer adds a significant amount of red LEDs, producing a spectrum that does not work well but will test well. Individual coloured LEDs always have higher photon efficacies than their white counterparts, thus increasing the photon output. Unfortunately, unscrupulous manufacturers in our industry have produced golden samples and sent them for testing. They have submitted the results for listing on the DesignLight Consortium (DLC) with close but confusing names to their generally available products. They are trying to trick you with good old-fashioned bait and switch. Large commercial operations with deeper pockets might want to consider sending a few recently-delivered LED grow lights to a testing lab to verify they actually got what they paid for.

Photon Efficacy and Dimming For most of my career, I have proudly spouted that when LED fixtures get dimmed, they gain efficacy. While it is true that the LED array will increase in efficacy when dimmed, the total “system” efficiency goes down. What happens to the driver (power supply) when dimming is the issue. They are designed to be run at or near full capacity. The LED array efficacy gains from dimming are not great enough to offset the losses from the driver. I experienced this firsthand while developing an LED grow light fixture. I used a 480-watt driver for the project, initially running the fixture at 320-watts. When the specifications changed it into a 400-watt fixture with the same LED bars, the efficacy increased ~5%.

ALL PHASE Craft Powder Base Nutrient & Additives VEG+BLOOM features 3 revolutionary one-part base powder nutrients and 2 additives in the UK. Catering to soft or hard water EC’s. We’ve also extensively researched in-house which mediums work best with our formulas. Our ingredients are locally sourced, refined and always batch tested for quality assurance to ensure consistency. Our all-phase one-part base powder formula was fabricated so that you could simply use your local water source as long as it fell between 0.0-0.7 EC. No other company offers this as they always recommend using RO water, which can be costly.

Base Nutrients: RO/SOFT is our most universal and popular one-part base nutrient. A hybrid of synthetics and organics; a pH stable formula for those who have small or large containers and a start water of 0.0-0.3 EC. It is completely soluble in RO water and built for coco, rockwool, or soil. TAP/HARD is a revolutionary pH stable formula for farms that have hard water 0.3-0.7 EC. No other company offers this as “water chemistry” is difficult to educate. With TAP/HARD you can potentially skip the costly RO water filter system and also save on the cost of water. Due to a higher pH in hard tap water, this formula is buffered appropriately so the use of large amounts of pH down can be avoided. Best used in coco and rockwool. DIRTY is a comprehensive formula for those who have a start water of 0.0-0.7 EC and are growing in soil or peat based mediums indoor or outdoor. Enhanced with humics, fulvics, crab meal extract and compost tea powder, this base was intended to provide the benefits of both synethetic and organic additives giving you extra bag appeal.

Craft Powder Base Nutrient & Additives

VEG+BLOOM encourages growers to spend less on extra additives and less time on the mixing and measuring (less human error) and more time on the plants, resulting in exceptional and consistent harvests. Save water, shipping costs, shelf space and minimize human error. Are you ready to reduce your variables?

Additives: PUSH is our foliar spray additive used during vegetative growth that includes bio available calcium, silica, plant stimulants and kelp. The plant hormones allow for cells to divide faster, reducing your overall veg cycle, while increasing cell wall strength and vigor. SHINE is our best product, a flowering bloom additive formulated with phosphites and organics such as compost tea powder for enhanced terpene and resin production. SHINE can be used not only in conjunction with our full nutrient line but can also be used with other base nutrient lines. Distributed in the UK by:

hydroponic-research.com

PHOTON EFFICACY

When looking for your nex t light, make sure the numbers add up

PPE vs PBAR There are two different ways of looking at photon efficacy. The most common is called Photosynthetic Photon Efficacy (PPE). This is a measurement of the number of photosynthetically active photons that fall into the PAR (400-700 nm) range. If your light produces photons outside this range, the overall PPE will be lower as they are not counted in the equation.

Large commercial operations with deeper pockets might want to consider sending a few recentlydelivered LED grow lights to a testing lab to verif y they actually got what they paid for

credit: www.activegrowled.com

A second method gaining in popularity is called Plant Biologically Active Radiation (PBAR). PBAR is difficult to explain as people define it in different ranges. Some use 300-800nm, while others use 350800nm or 280-800nm. This relatively new term is trending towards the whole range (280-800nm). Time will tell how this term ultimately gets defined. Since PBAR considers all the photons emitted from the fixture, its efficacy will be greater than PPE. It’s simply a larger top number divided by the same bottom number.

How Photon Efficacy Became “Real” for me I live in Colourado, and it gets pretty cold here in the winter. Being a basement grower, I’ve never dealt with excessive heat when using LEDs. Until recently, I had been using a ~4-year-old light. It had low photon efficacy to start due to the LEDs available when it was made. Over time, it got worse, as it contained LEDs that are now known to begin wearing out prematurely. More watts go directly into heat as it wears out instead of creating light.

I decided to switch out the aging light with a new one. I immediately began having heat issues but not one I am used to tackling – a lack of heat! I tried all the obvious things to warm up the grow. I slowed the intake and exhaust fans down to a crawl and changed the heating vents to direct more hot air into the room. Still, I had no success. When I grabbed onto one of the bars on the light, it all became clear. With higher photon efficacy, this new light produced more light and less heat than its predecessor. To sum up, understanding and calculating photon efficacy is not that difficult. When looking for your next light, make sure the numbers add up. If they don’t, walk away. If the manufacturer can’t perform this simple calculation accurately, you should not purchase the light from them. You will be surprised how many times many of them get it wrong! 3

Bio

Christopher Sloper is the author of “The LED Grow Book” and the VP of Lighting Technology at Global Garden. When he is not geeking out about plant science, he can be found working in his garden or riding his bike around his neighbourhood. He can be reached at sloper@globalgarden.co.

BY MARTYNA KROL

My New Addiction:

Fermentation T

he art of fermentation is addictive; there’s no doubt about it. It began with the simplicity of beetroot kvass in my house, followed by some sauerkraut and a few fruity and boozy experiments. So what I came

across last summer was surprising and a bit strange to understand at first - a lot of my fellow Poles seemed to be well into making their own vinegar, yet the fermenting groups in the UK were not mentioning it all.

VINEGAR FERMENTATION

Googling the benefits of vinegar is guaranteed to take a day out of your life When I think of vinegar, I think of fish and chips, of course. The British obsession with malt vinegar over chips, salt and vinegar crisps, and balsamic glaze were about the only reference I could make. And yet, the witches on the continent were showing off their colourful bottles, praising the health benefits and admiring the plethora of flavours. I just had to try it, even if I never intended to use them. Fast forward four months, and I find myself with 26 different kinds of vinegar and only the Fast forward four snow and frost holding me back from madly bottling more. and I find myself

The Process And History

months, with 26 different kinds of vinegar and only the snow and frost holding me back from madly bottling more

Tomato and basil vinegar (day 1)

Since the topic of Lacto-fermentation has been covered in the previous issue, we can compare its process and benefits to the art of vinegar making, also known as acetic fermentation. In short, it is a process in which alcohol is converted into acetic acid thanks to a bacteria group called Acetobacter, more particularly, A.aceti. That’s the same bacteria that will turn wine into vinegar; in fact, the meaning of the word vinegar is sour wine.

Traces of vinegar were found in Egyptian urns, but the oldest records of vinegar use go as far back as the Babylonians, circa 3,000 BC. As with Lacto, the official data on the specific type of bacteria - the acetic acid bacteria - was discovered by biology hero Louis Pasteur, a French microbiologist who studied lactic acid bacteria with Elie Metchnikoff. Strawberry vinegar (day 1)

Strawberry vinegar (December)

The Benefits Googling the benefits of vinegar is guaranteed to take a day out of your life. The low pH of the solution seems to be lethal to a lot of nasty bacteria, be it in our gut, on our skin, or surfaces around the house. There are many varieties of vinegar with different medicinal properties and uses. The most famous (or hipster, if you ask my husband) of all kinds of vinegar, apple cider vinegar, has been lately hailed as the ideal product to aid indigestion and support the digestive tract. It stimulates the stomach juices, synthesises digestive enzymes, and helps in breaking down fats. In popular literature, it has been advertised as having weight loss properties. It stabilises the stomach acid and helps in getting rid of heartburn. Historically, Cleopatra was known to drink a glass of water with vinegar after each feast, which was said to contribute to her having the perfect figure.

Vinegar is also highly cooling and has antiseptic properties. When spread on the skin, it evapourates quickly and offers a soothing effect, making it an excellent first aid for mild burns, including sunburn. It’s used as a skin tonic and a hair wash thanks to its low pH, which repairs damaged hair structures, making it shinier and preventing it from falling out. I have even read that it will help get rid of fever in babies when used as a delicate body wash or a head compress.

Household and Culinary Use In the house, vinegar can unblock the drains, clean surfaces, bathrooms, and bring perfect shine to windows. Bacteria and pathogens stand no chance against it, so it’s worth trying it out. The list of benefits seems never-ending!

Guanokalong

Creating healthy plants with excellent tasting crops! 100% organic bat guano fertilizer • www.guanokalong.nl

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VINEGAR FERMENTATION

Vinegars of 2021 (the blackberries dropping to the bottom are a sign it’s ready to be bottled)

All vinegar will mature with time, and like wine, the longer they rest, the better they are

Grape, blackberry, and raspberry vinegar

Patience, Friends Now, the great wait starts. Your vinegar will need to stay at room temperature for at least three months, and be warned; it will smell a bit funky as the alcoholic fermentation takes charge. After some time, the smell becomes more vinegary and pleasant. Often, the contents will fall to the bottom; this is a sign that your vinegar is ready to be poured into a clean bottle and left in the cellar or a cool spot for at least six months, or even better, a year. All vinegar will mature with time, and like wine, the longer they rest, the better they are.

The Spotlight Two products deserve special mention for vinegar - oxymel and mustard. Oxymel is a one-to-one mix of apple vinegar (often steeped with fruits or made with fruits to start with) and honey. Its medicinal

benefits are incredible in strengthening the immune system and fighting infections. After you’ve bottled your liquid vinegar, you can combine the apple (or raspberry, blackberry, etc.) pulp left behind with mustard seeds, honey, salt, and turmeric, creating beautiful homemade mustard in just six weeks. Making vinegar is fascinating, and judging how the Lacto-fermentation trend has skyrocketed in the western world, vinegar is next in line. 3

BIO Martyna Krol is a vegetable grower, natural bee-

keeper, and edible spaces designer. She is a lover of all soil and urban farming techniques and is the former head of growing at Incredible Aquagarden.

SOILS PLANT CANOPYJAWS TRAINING

BY AV SINGH

Takin’ A Bite Out of Labour

aking the switch from liquid nutrients to growing in living soil organic (LSO) systems evokes images of freeing yourself from measuring flasks and sticky plastic bottles. In reality, many LSO growers are hunched over with dusty measuring cups as they scratch in some bone meal or seaweed powder to give their plants a needed boost of phosphorus or potassium. The notion of individually top-dressing dry amendments by hand to thousands of plants is unfathomable. Still, even at a smaller scale, this approach can be cumbersome, time-consuming, and lead to inconsistent fertiliser application.

So, how do we make Just Add Water Super soils work for short lifecycle plants? Microbes 61

DRY SOLUBLE NUTRIENTS Efficient nutrition

www.goldlabel.nl

JAWS SOILS

Growers expressed their creativity through their selected amendments; one recipe favoured greensand over basalt rock dust, while another chose bat guano over blood meal or horse manure versus hen manure

The solution? [queue in the JAWS movie theme song] - Just Add Water Super soils (JAWS).

Understanding how and when your amendments

soybean meal af ter microbes like bacteria consume the soybean meal. Of ten, they too get consumed by other microbes, the result of N being provided in a form that plants can use. The nutrient cycling of organic amendments requires time. As a result, when JAWS soils were introduced to cultivation strategies with shor ter lifecycles (perhaps a 4-week veg period), growers had mixed results, of ten needing to supplement with more nutrients in early f lower.

become available to the These nutrient-dense soil recipes allowed guerilla growers the plant is imperative in oppor tunity to “set it, and forget it”. They blended rich combinations designing JAWS soil of organic amendments in with bulk growing media consisting primarily of peat moss, compost, and at times, perlite. Growers expressed their creativity through their selected amendments; one recipe favoured greensand over basalt rock dust, while another chose bat guano over blood meal or horse manure versus hen manure. Many In the ‘90s and early 2000s, dogmatic growers insisting on online cultivation forums had only locally-sourced minerals and countless Super Soil recipes, nutrients like crab meal, storm cast and many of the pioneers’ kelp, and an assor tment of farm formulas still exist today, like manures may have unknowingly Subcool’s, Clackamas Coot’s introduced the concept of “terroir” and The Rev’s. These nutrientto their gardens through the creation of these JAWS dense recipes provide ever y thing and more for good soils. For the most par t, early adopters of JAWS soils yields and quality. Still, the demands and expectations were satisfied by their simplified feeding schedule that of today’s more competitive market are pushing for only required water. Their success was largely because faster yields and better quality. The logical answer to they maintained significantly longer vegetative periods this dilemma is to soup up the recipe and go with the (in excess of 8 weeks), but the same was not true when “more is better” approach. But, expectedly, as with adapted to shor ter life cycle plants. most things in life, the “more” solution will of ten lead to detrimental effects. Super soils need to be created Why is veg time relevant? Growers were of ten drawn with a nutrient-balanced approach. Other wise, cer tain to JAWS soils because the ingredients were organic. elements will outcompete others and limit a plant’s Organic nutrients like alfalfa or feather meal are ability to take them up. For example, soils designed not soluble and only become plant available through with too much potassium (K) may show signs of nutrient cycling created by microbes. A plant’s roots calcium (Ca) or magnesium (Mg) def iciencies despite can only take up the nitrogen (N) in protein-rich the soil being chock full of both.

JAWS SOILS

So, how do we make Just Add Water Ingredients with higher amounts Super soils work for shor t lifecycle of carbon require more microbial plants? Microbes. The secret sauce digestion before becoming plant in changing a nutrient-dense soil available. For example, alfalfa meal A JAWS soil is not a recipe to a JAWS soil recipe is or feather meal will release their means to an end; it the introduction of billions and N much slower than bloodmeal. billions of microbes. Compost and In designing a JAWS, you want to is not trying to take worm castings can be a good star t. make sure nutrients are available away the creativity The consor tia of species found in in the form plants wish to use of the grower. On the quality compost and worm casting when they want to use them. contrary, it allows the should have thousands of bacteria, Plants love nitrate-nitrogen in the archaea, fungi, protozoa, nematodes vegetative phase and would prefer grower to focus more -- essentially a diverse village of N in the form of amino acids or on pruning, trellising, workers. However, you may not ammonium in later stages of life. and ensuring the need that much diversity at times, To perform this, appropriate right environment and you will choose a microbial amounts of fast-release and slowinoculant that lacks diversity but has release N-forms. Understanding rather than assuming the numbers. Microbial inoculants how and when your amendments what the plant wants often include a handful of species become available to the plant is to eat and when it that work well together and have imperative in designing JAWS soil. wants to eat fairly defined roles. For example, an inoculant may consist of bacteria A JAWS soil is not a means to that work well at nutrient cycling an end; it is not trying to take or stimulating a plant’s immune away the creativity of the grower. function. It may also include some On the contrary, it allows the fungi that help protect the roots grower to focus more on pruning, from pathogens. The sheer number trellising, and ensuring the right of microbes in these inoculants environment rather than assuming speeds up nutrient release to meet what the plant wants to eat and the plant’s needs. This interface between microbes and when it wants to eat. Moreover, for those growers who the plant honors millennia of co-evolution where plants can’t help themselves, they may choose to supplement have figured out what their roots need to provide as with aerobic compost teas, extracts, fermented teas, exudates (foods) to get the specific microbes to do what juices, and other elixirs as ways of expressing their they need them to do. uniqueness while getting higher yields, better quality, and saving on labour. 3 Choosing the “right” amendments for a JAWS mix may seem like an ar t where the grower has some special “goBIO Av Singh, PhD, PAg is an advocate of regenerative organto” ingredient that makes all the difference. While there ic agriculture serving various organisations including Regenermay be some merit to that, designing JAWS soil requires ation Canada, Navdanya, and the Canadian Organic Growers. some science. Organic nutrients have varying release rates, largely owing to the carbon to nitrogen (C:N) ratio.

Grow Room Ventilation 2.0

How LE LEDD Grow Lights Have Moved The

Goal Posts

GROW ROOM VENTILATION BY EVEREST FERNANDEZ

rowers moving from HPS to LED grow lights need to adapt their ventilation strategies to maintain yields and maximise the benefits. But that’s not all that needs to

change, writes veteran indoor grower Everest Fernandez.

Growers have historically ventilated their grow rooms for three reasons: 1. 2. 3.

To remove hot air from their growing space and replace it with cooler air To reduce humidity levels To replenish carbon dioxide levels

There it is—your humble extraction fans killing three birds with one stone—three problems, one solution. Ventilation (aka air exchange) remains the most energy-efficient method to maintain a healthy indoor growing environment. Out with the old, hot, moist, carbon dioxide-depleted air, and in with the new, cool, moderately humid, fresh air. Of course, due to geographical location, some growers have never really enjoyed the option of ventilating their grow rooms. Cultivators living in Florida or Phoenix are obliged to go the sealed room route, relying on an energy-hogging mix of air conditioners, dehumidifiers, and supplemental carbon dioxide rather than ventilation simply because the ambient air available is too hot, too dry, or too humid to draw into their grow rooms. However, ventilation offers the most energy-efficient climate control for indoor growers living in cooler climes (i.e. Portland, Seattle, Alaska, British Columbia, Michigan, New England, etc.).

LED Grow Lights Have Changed the “Priority Order” of Grow Room Environment Challenges Plants have not changed since the advent of LED lighting technology, and neither have the above three reasons for ventilating our gardens. What LED grow lights have changed is the order or relative magnitude of these challenges.

Ventilation (aka air exchange) remains the most energy-efficient method to maintain a healthy indoor growing environment

band. It’s the main reason we feel the warmth from the Sun. And plants, especially those native to higher altitudes in the sub-tropics, use this infrared radiation to warm up their plant tissue, not unlike a cold-blooded reptile basking in the Sun. Traditionally, indoor growers would aim to keep air temperatures around 75 – 77 °F (24 – 25 °C) for most warm season herbaceous annual plants to offset the warming effect of the significant infrared generated directly from their HPS and MH lamps. However, modern LED grow light fixtures emit virtually no infrared directly from their diodes. (Although a small amount of infrared output is now being incorporated into some more recent LED fixtures.) To compensate for this comparative lack of infrared radiation, indoor growers using LED grow lights run their rooms warmer; they elevate the daytime air temperature in their grow rooms to the region of 82 – 85 °F (27 – 29 °C). In these markedly warmer conditions, plant tissue doesn’t miss the warming effect of infrared so much. It can reach sufficient warmth via convection heat transfer with the air to drive metabolic processes.

High Air Temperatures Aren’t Such a Big Issue Back in the High Pressure Sodium (HPS) and Metal Halide (MH) days, the main bogeyman in practically every indoor garden was high daytime air temperatures. Heat production was wrapped up with light production. Not only do HPS and MH lamps generate plenty of convection heat (heating up the air), they produce plenty of infrared radiation too. Now, it’s worth pointing out that infrared is not an intrinsically bad thing. Over half of the incident solar energy reaching our planet from the Sun falls into the infrared

Not only do HPS and MH lamps generate plenty of convection heat (heating up the air), they produce plenty of infrared radiation too.

GROW ROOM VENTILATION

To compensate for this comparative lack of infrared radiation, indoor growers using LED grow lights run their rooms warmer; they elevate the daytime air temperature in their grow rooms to the region of 82 – 85 °F (27 – 29 °C)

Massively Elevated EC / TDS with LEDs It’s also worth noting that LED growers run their nutrient solutions at significantly higher EC than growers running legacy lighting. In fact, commercial growers cultivating in zero-CEC media, such as Rockwool, will start their rooted cuttings at 3.0 mS (instead of the typical 1.2 mS) and go up to 7.0 or 8.0 mS in flower. Yes, you read that right—that’s 3500 or 4000 PPM! That’s three or four times the typical nutrient concentration with legacy lighting. Admittedly, these are seasoned commercial growers who aren’t using your standard GROW A and B and BLOOM A and B formulas. They’re mixing up their primary and secondary nutrients using specific salts, not blended stock solutions, keeping their nitrate levels low, and elevating magnesium levels significantly. (A decent target ratio of calcium to magnesium ions is 2:1.) The higher osmotic pressure created by these strong nutrient solutions helps to offset the lower transpiration rates generated by LEDs.

But wait… even this seemingly small change can have significant knock-on effects for your grow room’s environment and the plants within it. 1. Now, your thermostatically controlled extraction fan isn’t working as hard Okay, so you’ve moved the set-point of your thermostatic fan speed controller up from 75 °F to 79 °F so that your grow room stays warmer. The set-point is the “trigger temperature” where your inline fans will go to max speed to try and stay within your desired temperature range. Now that your set-point is higher, your fans won’t kick into max power as much, meaning the overall amount of air exchange in your grow room could be massively reduced. This inevitably leads to higher humidity levels. 2. Your nutrient solution will probably be warmer If your nutrient solution reservoir is located within the same room as your grow space, it will be subject to higher air temperatures. Depending on the volume of your reservoir, growing style (recirculating or run-towaste) and rate of usage, it may be necessary to keep a closer eye on nutrient solution temperatures. Warmer nutrient solutions equate to lower dissolved oxygen levels which can lower plant metabolic rates. 3. Wet/dry cycles may be quicker Warmer nutrient solutions and overall warmer plant tissue will draw more moisture through the root zone as a whole, meaning plants could seem “thirstier”, leading to more wet/dry cycles in the growing media. This can increase the risk of salt build-in up your soilless growing media, especially when running more concentrated nutrient solutions.

ENHANCED FULL SPECTRUM MULTI-DRIVER CONTROL 10-BAR

8-BAR

6-BAR

4-BAR

600/750W DE-HPS: COVER 1.2 x 1.5m @ 45cm 1000/1100W DE-HPS: COVER 1.5 x 2.1m @ 60cm

GROW ROOM VENTILATION

If you ca n’t decid e betwe duct size en two s, go for the large r option

So what do growers need to do to get the most from their LED grow lights? Don’t under-specify your inline fan and carbon filter If you can’t decide between two duct sizes, go for the larger option. Not only will it run more quietly for the same amount of air movement, but it’s always a good idea to have some power in reserve. Calculate the cubic feet of your active growing area (length x width x height) and multiply this total by 2.5. This gives you the CFM rating you should be looking for in your fan—taking into account carbon filter pressure drop and a reasonable amount of ducting. Use our fan size calculator to check what size fan and filter you need for your indoor garden. Use humidity and temperature to guide your fan speed Consider upgrading your environmental controller so that your extraction and intake fans kick into max speed whenever your relative humidity rises above a set-point, not just temperature. Sure, many LED growers are running more humid grow rooms these days to counter the higher temperatures and achieve a desirable vapour pressure deficit (VPD). Just remember how critical proper air exchange is for your grow tent or grow room. Some growers run dedicated dehumidifiers for their grow rooms—especially during the winter months and during the nighttime period.

Consider upgrading your environmental controller so that your extraction and intake fans kick into max speed whenever your relative humidity rises above a set-point, not just temperature 3. Grow more plants, prune harder, flip earlier LED grow lights are an incredible technological upgrade in some respects, and there is a wide variety of form factors available. Most home growers use multi-array “spider” style LED fixtures, and these certainly seem best suited to illuminate smaller plants rather than the huge, gangly beasts of some old-school HPS rooms. Higher numbers of smaller plants are the way to go. Use topping and pruning techniques to increase the number of flowering sites. Very short vegetative periods of just a handful of days with brutal pruning and removal of lower growth tips are the way to go. 3

BIO

Everest Fernandez is a well-respected industry educator, veteran hydroponic grower, and grow light enthusiast based in France. He works primarily as a marketing and cultivation consultant and was the founding editor of Urban Garden Magazine in the UK, US, and Canada. He also writes and researches for the popular hobby horticulturist YouTube channel, Just4Growers.

The new 100% organic, 100% vegan nutrient line has been formulated to run clearly through drippers and irrigation lines.

BY ALBERT MONDOR, HORTICULTURIST AND BIOLOGIST

Mini Veggies

big BIG yields 74

MINI VEGGIES

Eggplants are particularly demanding, and growing them can be challenging to novice gardeners, but they do exceptionally well in containers

roductive and less demanding than the largefruit varieties, several small-sized eggplants, sweet pepper and tomato cultivars have been created

especially for container growing in urban settings.

Eggplants Eggplant seeds should be sown indoors in late March or early April, about eight weeks before heading out to the garden. Since aubergines do not like transplanting, it is best to place the seeds in individual pots filled with soil containing compost, sphagnum peat moss and perlite. Sow two to three seeds per compartment to ensure that one seedling forms. Sow seeds at a depth of 6 mm (1/4 inch). Eggplant seeds germinate at temperatures between 26 and 30°C. Place the seedling containers on a heat mat to keep the substrate warm. Cover the seedlings with a clear plastic dome to maintain decent humidity levels during the first two or three weeks. Open or remove the dome when condensation forms. When the first two true leaves have formed, transplant the seedlings into 4-inch pots, burying their stems about an inch below the soil surface. Eggplants need a lot of light, so consider placing the seedlings under an LED lighting system designed for growing plants. Eggplants are particularly demanding, and growing them can be challenging to novice gardeners, but they do exceptionally well in containers. Plant them in rich, loose and well-drained soil located in a warm and very sunny place, well protected from the wind. Be sure to place them outdoors only a few weeks after your region’s last frost, acclimatising them for several days before.

Patio Baby eggplant Some small-sized eggplant cultivars well suited to container culture include: • • •

Applegreen Little Fingers Gretel

• •

Patio Baby Fairy Tale

Consider placing a black plastic tarp on the soil surface of the eggplant containers. This trick will raise the earth’s temperature, keeping it between 27 and 32°C. Score the plastic with a knife and place the plants in the opening.

Fairy Tale eggplant

credit: growjoy

Several small-sized eggplant cultivars have been created especially for container cultivation on patios, terraces and balconies. Grow these varieties in large black pots. Don’t hesitate to add mycorrhizal fungi to the soil and a few handfuls (100ml per plant) of a slow-release granular natural fertiliser (formulation 5-3-8). Water your potted eggplant plants regularly, twice a week during the summer.

MINI VEGGIES

Peppers The late winter or early spring is the best time to sow pepper seeds indoors. Then, depending on the region, transplant seedlings outside six to eight weeks later, towards the end of May or June. Sow seeds ½ inch deep in a container of moist potting soil consisting of compost, sphagnum peat moss and perlite. Place two seeds in each compartment to make sure at least one takes. If both seeds germinate, keep the stronger one and cut the other off with scissors.

You can plant peppers outside one or two weeks after your region’s last risk of frost. Transplant them into loose and welldrained soil enriched with compost in a sunny place that is well-protected from winds. Plant your peppers in a substrate composed of compost and sphagnum peat moss if you prefer to grow them in pots. Opt for stocky cultivars that produce small fruits.

Like eggplants, sweet peppers need warmth and lots of light to grow and produce fruits—place seedlings under an artificial LED lighting system for 12 to 16 hours a day. The optimum temperature for the germination of pepper seeds is between 24 and 30°C. Keep the soil warm by placing seedlings on a heat mat.

Before planting, cut the first two leaves from the bottom of each plant so you can bury the stem up to the first node. This ensures better rooting and promotes better water and nutrient uptake. When planting, provide each pepper plant with three to four handfuls (100 mL) of a natural, slow-release granular fertiliser rich in nitrogen and potassium (5-3-8). You can also add a mycorrhizal fungus when planting. When the first flowers turn to fruit, regularly spray liquid kelp on the plant’s foliage. This fertiliser is rich in potassium and micronutrients essential to obtaining very sweet peppers. Less demanding than the large-fruited cultivars, the five smallsized sweet pepper cultivars below are perfect for container culture on patios, decks, terraces and balconies. • • •

Golden Baby Belle Lunchbox Mix Lemon Dream

Credit: Johnny’s Selected Seeds

Like eggplants, sweet peppers need warmth and lots of light to grow and produce fruits—place seedlings under an artificial LED lighting system for 12 to 16 hours a day

credit: Pepperworld Hot Shop

Three or four weeks after germination, when the first two true leaves have formed, transplant the plants into 4-inch pots, making sure to bury their stems a few inches below the soil.

• •

Mini Bell Mix Sweet Yellow Stuffing

Lunchbox Yellow

ENZYMES BY DEFINITION

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Made In the USA

MINI VEGGIES

Sweet ‘n Neat

Humans have developed almost 14,000 different cultivars of tomatoes over the centuries!

Tomatoes Tomatoes are very popular and undoubtedly one of the most consumed fruits on the planet. Humans have developed almost 14,000 different cultivars of tomatoes over the centuries! Late March or early April is an excellent time to sow tomatoes indoors. First, plant seeds about a half-inch deep in a potting soil made up of compost, sphagnum peat moss and perlite. Then sprinkle the potting soil with lukewarm water. About 20 days after germination, snip the plant’s first true leaves and place the young seedlings in 4-inch pots, burying their stems below the soil’s surface. Tomato plants need a lot of light to grow, so start them under LED lighting for 12 to 14 hours per day. Transplant tomato seedlings outside six to eight weeks later, in May or June. When you plant a tomato seedling outside, make sure the base of its central stem is placed a few inches below soil level. By cutting off the first leaves attached to the main stem, you can place it 4 to 6 inches below the ground surface. This technique promotes an extensive root system that can absorb more water and nutrients.

Credit: Albert Mondor

Tomato plants require heat and intense sunlight to produce fruit, so plant them in a place that gets 6-8 hours of sun and is well protected from the wind.

Sweet Valentine

Whether grown in containers or the ground, provide plenty of compost to your tomato plants. In pots, tomatoes benefit from a substrate composed of compost, sphagnum peat moss and perlite. In addition, some growing mixes contain mycorrhizal fungi, which helps increase the growth and development of tomatoes. Tomatoes love humidity, so be sure to water your plants deeply two to three times a week, ideally with lukewarm water. Do you want to grow tomatoes on your balcony this summer? Several compact cultivars meet the needs of urban gardeners. These tomato varieties are so compact that they can even be grown on walls! • • •

Rambling Red Stripe Sweet ‘n Neat Sweet Valentine

• •

Tumbler Tumbling Tom Yellow

BIO Passionate about environmental horticulture, urban agriculture and extreme landscape design, Albert Mondor

has practised his craft for over 30 years and created numerous gardens in North America. In addition to teaching courses and lecturing at conferences across Canada, his weekly gardening column has appeared in the Journal de Montréal and the Journal de Québec since 1999. In April 2018, Albert Mondor published Le nouveau potager, his tenth horticultural book. He is a regular guest and contributor to radio and television programmes and his hosting The Trendy Gardener spots broadcasted on Météo Média and online. You can also read his blog called Extreme Horticulture at albertmondor.com. Follow Albert on Facebook: fb.com/albert.mondor

BY BETTY GREEN

Green Manure Optimise Your Soil This Year

Low-growing green manure like trefoil is excellent for covering the bare ground between rows of tall crops like sweetcorn and avoiding weed growth.

Bird’s-Foot Trefoil (Lotus corniculatus)

Try growing vetch throughout the winter underneath blackcurrant bushes. Then, hoe the vetch off in the spring and leave the foliage to decompose. The blackcurrant bush will take up the extra nitrogen when it needs it most.

Hairy Vetch

GREEN MANURE

Food crops need several nutrients in relatively large quantities during the vegetative or growth period, especially nitrogen

o grow healthy, tasty vegetables, getting nutrients into the soil before planting is critical. Food crops need several nutrients in relatively

large quantities during the vegetative or growth period, especially nitrogen. Unless your soil is regularly replenished with nutrients, it can quickly become barren and unyielding. Digging in organic matter or compost will help readdress the balance. Another option is green manure. Green manures are plants that are specifically grown to benefit the soil. They do this in several ways: • • • •

By adding valuable nitrogen By improving drainage and water retention By repressing weeds By enticing advantageous insects and predators

Green manure plants are quick growers, meaning the soil can benefit from green manure just a few weeks after sowing.

How It Works Nitrogen Fixing The roots of green manure plants run deeper than other crops grown in the garden, so they can source nutrients from a vast area. Plants hailing from the legume family, such as clover, alfalfa, soybean, peanut and rooibos, absorb nitrogen from the atmosphere and fix it into their roots. Legumes have symbiotic rhizobia bacteria living within their roots. The bacteria produce nitrogen compounds and store them in nodules on the roots, which are then used to grow the plant. In return for nitrogen, the plant supplies the bacteria with photosynthesis-derived sugars and other nutritional elements to keep them alive. Once a green manure plant hits maturity, dig it back into the soil to allow its nutrients to return to the earth so crops can take advantage. This nitrogen influx also helps provide for the soil’s microbial life, increasing its health tenfold and creating a healthy and rich growing medium.

Those following no-dig techniques can still work with green manure. Instead of digging in, leave the cuttings on the surface to act as a mulch or hoe it in. Improved Soil Structure Green manures can help correct any problems with soil structure, whether too heavy and clay-like or too sandy and delicate. The green manure has a broad and deep burrowing root mass and can aerate dense soils for better drainage. In addition, the roots bind to the soil particles in light, sandy soil, acting as a sponge to soak up nutrients. Weed Suppression Nature rapidly occupies bare soil, generally in the form of weeds. A cover crop of quick-growing green manure, like mustard, will snuff out any pockets of rebel weeds, saving you a lot of work in the garden. White clover is a great long term cover crop, eventually suffocating the weeds and building up precious nitrogen stores in the soil. Pest Control The bright flowers of crimson clover or blue tansy attract bees and hoverflies, both of which are excellent weapons against aphids! Research shows that some flying pests can become confused and deterred if they cannot recognise the outlines of their food plant. Try planting brassica with trefoil or vetch to conceal the silhouette of the crop and prevent cabbage root fly. Slug predators like beetles and frogs love the damp environment of a green manure cover crop.

Practical Ways To Use Green Manure If you have inherited overworked soil in a new garden or allotment, try growing only green manure for the first season. Although you will have to wait longer for your veggie crops, when you do start growing, your soil will be much healthier and reward you with a much better yield. You can sow some green manure crops in autumn to keep the soil covered during winter. Grazing rye or winter vetch will fit the bill perfectly. Then, once spring is on the way and the air warms up, dig the crops into your soil to get the media teeming with nutrients in anticipation of your summer veg haul. Green manures can be used as catch crops, which are quick-growing plants that can be sown between seasons to use soil that would otherwise be standing empty. Try planting green manure after harvesting crops like potatoes; mustard is a good option. 3

Bio

Betty Green has two passions in life: plants and food, which is perfect considering the two go hand in hand. Betty is a dedicated gardener and self-taught cook who is big on organic produce and sustainability. With a large family of four children to feed, she has been slowly increasing her portfolio of garden produce for her growing repertoire of delicious recipes. Betty loves writing about plants, cooking, and sustainability. 81

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BY RICH HAMILTON

Quenching The Thirst

Of Food Crops With

Dry Farming B

efore irrigation systems, farmers growing in hot and arid climates could still produce various crops using dry farming techniques.This garden-

ing method doesn’t necessarily lead to the biggest yields and has waned over time, but it is becoming popular again thanks to its eco-friendly benefits.

DRY FARMING

This gardening method doesn’t necessarily lead to the biggest yields and has waned over time, but it is becoming popular again thanks to its eco-friendly benefits

Changing Climates Due to climate change, drought is becoming more common in many parts of the world. As a result, farmers and gardeners are looking for alternative crop production methods that are less reliant on irrigation and can handle inconsistent water supplies. Dry farming techniques are standard in parched regions such as the Mediterranean, Africa, and in recent years, Southern California. It is still widely used in southern Europe and other areas with extended dry seasons. Crops grown via dryland farming include some of the world’s best and most costly wines and oils. In some locations in the south of France, it is illegal to irrigate the land during the growing season because it changes the quality of the wine.

With little to no extra irrigation or fertiliser requirements, production costs for dry farming are lower than traditional farming techniques and are more sustainable

A Natural Approach Drip irrigation, controlled sprinkler systems and the genetic engineering of drought-tolerant crops are often implemented in the battle against excessive water use. Dry farming, however, is a more natural approach. It uses the moisture accumulated in the soil from the previous rainy season. Soil tillage is used to work the earth and bring up water. The ground is then compacted to seal in the moisture. As a result, crops can grow without additional irrigation during the dry season. With little to no extra irrigation or fertiliser requirements, production costs for dry farming are lower than traditional farming techniques and are more sustainable. This principle of dilution at work is another benefit of dry farming. The idea is that less water in the soil translates to lower water content in the harvested crop. This, in turn, means a better, more potent flavour. So, while you are not getting the most significant yields possible, you are making up for it in high quality, tasty produce. Farmers are beginning to turn to dry farming techniques, experimenting with crops ideal in more arid conditions or mature early and have mini or dwarf cultivars. These crops include beans, potatoes, tomatoes, squash, and melons.

How Dry Farming Works How do dry farming techniques store rainfall in the soil for later use? Standard practices involve amending the soil with

aged organic matter twice a year and double digging the earth for aeration in autumn. Furthermore, farmers will tend the soil lightly after every rainfall to prevent crusting. Plants are generally spaced further apart than average and can be thinned out when they are an inch or two tall. Weeding and mulching around plants help maintain moisture, repel weeds, and keep roots cool.

Dust and Stubble Mulching Dust mulching is used to deter the soil drying process. Dust mulching involves cultivating the soil by two to three inches to prevent moisture loss via evapouration. After harvest, leave any harvested crop remains or stubble mulch to act as green manure and stop the earth from drying out. Stubble mulching is only possible if the farmers are not planning on producing another crop from the same member of the stubble crop family, as this can promote disease. Therefore, some farmers will “clear fallow” where no crop is planted for a year, leaving only stubble mulch behind. This process is performed every other year in many regions, equating to about 70% of rainfall being captured and stored in the soil. Life has always found a way to flourish, even in the most waterless regions of the planet. While farming in these areas may seem like a contradiction, humans have been planting and harvesting these areas long before the invention of modern-day irrigation methods. If we want to live more harmoniously with our environment, maybe we should start having a little more faith in nature and look to the past for answers. 3

BIO An industry veteran with over 20 years of experience in a variety of roles, Rich is currently a business development manager for a large UK hydroponics distributor. The author of the Growers Guide book series, Rich also writes on all aspects of indoor gardening. He is also an independent industry consultant, working closely with hydroponic businesses worldwide.

Years

GROWING TOGETHER

BY MARTYNA KROL

Local

Growers WHO’S GROWING WHAT WHERE

in the U Kreland & I

1. Hullavington, Wiltshire

Chris Elliott - Happy Acres

Allotments are more than just spaces to grow food; they bring peace and motivation. Chris Elliot from Happy Acres turned his skills as a food technology and horticulture teacher into an inspirational resource for those who couldn’t leave their homes during the pandemic. His channel is full of practical tips on organising a plot on a budget, comparing digging and no-dig methods, making homemade fertilisers and improving the soil structure. During the first lockdown, Chris created a series of videos for kids to try out at home, such as bird feeder making, repurposing tins as pots and growing food from scraps, anything that keeps kids motivated. His videos were an excellent resource for homeschooling parents, and Sheffield schools and youth groups widely shared his videos. When life took a sad turn and Chris’ dad passed away, it was the allotment that brought him peace again. A friendly robin, a symbol of hope, rebirth and loved ones who have left this world came to keep him company as he was struggling with a fence which, he says, his dad would have put up in ten minutes. Suddenly, the allotment work became therapeutic; it gave him balance and a reason to get up. The need to help others fanned the flames of his passion, which led to collabourations with a food bank and creating new free and inspirational content. He has exciting plans for the future. Chris’ kindness and passion resonate, and as he says, “if just one person does something that I have shown them, then I have done my job”. Learn more about Chris and his work: facebook.com/groups/DCCKidz/ & bit.ly/34QBuwy allotment8acres youtube.com/c/HappyAcresAllotmentKitchen

2. Cuckfield, West Sussex

Sacha Brown - Queen of Seed Two decades of carefully curated soil, rich in mycorrhizal hyphae and producing astonishing results are the effect of Sacha’s passion (and lots of hard work). Her garden is a thriving pollinator habitat with dozens of flower and vegetable varieties blooming together happily. Digging has been long forgotten, swapped for mulching and soil creation; these are ways Sacha hopes to enhance the ground with which she spends so much time. In her opinion, gardening and vegetable growing should be simple and enriching. To help those at the beginning of their journey, she created a monthly seed subscription service with her own tried and tested varieties that she sends at the perfect sowing time with growing instructions and video tutorials attached. Her garden journal is full of carefully kept notes, design plans, plants ordered and tested over the past fifteen years, and probably some secrets, too. When looking at the photos of colourful flowers and unusual vegetables such as Choi Sum, one can only give in and start browsing the exciting seed collections Sacha has in her library. Her belief that everyone can grow something that benefits the Earth as much as ourselves, even in the smallest of spaces, is certainly one I can get behind. Learn more: queenofseed.co.uk queenofseed

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WHAT’S GROWING ON

Local

Growers WHO’S GROWING WHAT WHERE 3. Sheffield, South Yorkshire

in the U Kreland & I

The Food Works Farm

One of the positive effects of the 2020 craziness is the number of new gardens and farms created to help people access fresh food. The land that became the Food Works Farm was donated to the project by the urban park Green Estate in Sheffield to grow and share food within the local community. Fran Halsall designed the space and has been running it ever since with the support of a constantly expanding team of volunteers. 2021 brought their first harvests, an impressive 850 kilograms harvested from only 200 square metres of growing space. All the food is used in Food Works’ community kitchens, where nutritious meals are prepared and sold on a pay-as-you-feel basis. Throughout the last two years, their kitchen has supported NHS staff, key workers, and those affected by Covid-19 who couldn’t access healthy meals. The farm uses intensive cropping and interplanting methods, growing taller and lower plants together. The organisation is highly resourceful, reaching out to local networks to source materials and plants for free where possible. All collected surplus food is destined for use, and anything past the point of human consumption is composted, feeding the soil, the crops, and then the bellies. Learn more: thefoodworks.org/farm facebook.com/TheFoodWorksSHF @thefoodworksshf

4. Rowley Regis, West Midlands

Urban Herbs

All dads are heroes, and Mark Alexander’s son will be proud one day to learn that his dad’s achievements as a Seed Guardian did more good than all of Batman’s night escapades. Caring for quality seeds is not easy; the climate has changed, and so have the growing conditions. With many popular brands sourcing seeds from the same distributors, the strength and unique lineage of heirloom varieties are diminishing, often when the growing conditions aren’t similar to the final destination - our plots. Mark’s growing journey began with moving out of London, starting a family and getting an allotment. His passion for seasonal eating and reducing waste resulted in a carefully planned growing season, ensuring his family enjoys trips to the plot rather than the supermarket. Although he appreciates that modern cultivars and the rare hybrid have their place, Mark’s passion is to share the educational aspects of seed sovereignty, selecting seeds for the best genetic material possible and growing them in conditions local to the area. Many growers appreciate his efforts in helping launch the Guildford Seed Bank from a CSA farm through to allotment societies, local schools and community gardens. As he beautifully says, “we should be taking old principles, old varieties, and growing them in modern conditions. Looking to the future, not the past”. Follow Mark: facebook.com/guildfordseedbank @markhomegrowndad & @guilfordseedbank

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BY ADAM CLARKE

Ventilation,

Dehumidification and the Effect on your Environment and Plants

he most critical factor in indoor growing is controlled and tight environmental conditions. Producing the best plants will always be out of reach without this crucial puzzle piece. Of course,

there are other essential factors like lights, genetics, nutrients, and, of course, loving your ladies, but environmental is the key to it all.

To get the perfect plant, you need the perfect environment.

VENTILATION & DEHUMIDIFICATION

Cause and Effect Great lights vs. Bad environment You can have an incredible light with the best spectrum and all the power you could ever need, but without the right environment, the plants won’t use all that light. Great Genetics vs. Bad Environment In a room that doesn’t allow for the right transpiration or the optimal environment, plants won’t achieve their genetic potential. Great Soil and Nutrients vs. Bad Environmental Without the right environment, the plants will not uptake the correct nutrients from your growing media. As a result, the plants will suffer, and you will not get an optimum yield. No matter the case, an excellent environmental system will fix many issues in your space. For example, suppose you have powdery mildew (PM), as we know most growers do. In that case, keeping your environment stable and not having big humidity swings will be critical to preventing the PM from proliferating. Keeping too high relative humidity (RH) or two low RH will cause PM to thrive. We typically aim to keep our rooms 80-82°F at 60% during normal flower, which keeps the PM from getting a hold in the room. If you cannot control your lights-off swing in RH, then you will be kicking the PM back into high gear every lights-off cycle. The key, again, is to control your environment to a very tight “dead band,” the range in fluctuation we allow the temperature and RH to go up or down. PM is a good general example of a problem proliferated by a bad environment. When reading about controlled environments, there are a lot of ‘Buzz” words out there, but generally, they are all trying to help do the same thing. That is, to predict what the plants will do in the space and change how your environmental controls respond. Most systems on the market are designed to respond to changes in the environment. As you get into more sophisticated systems, you can start predicting what will happen in the space before you make a change. What if the air conditioning and dehumidification know there will be a demand for heat before the lights turn on? What if your dehumidifier knew you were about to water the plants or foliar spray? The answer is that if your environmental controls knew these things were about to happen, they could turn on in advance and prepare the room for the change. Every room is slightly different, so sometimes predicting can take a few cycles to learn how the room works. Once the controls know the space, then predicting gets easier.

Control Systems/Environmental Controls When looking into your control system, there are several factors to investigate. First, determine your budget and what you’d like to automate. The list of items is nearly endless in a grow, and cost can skyrocket depending on what you are looking to do. A standard offering of controls may consist of the following:

• • • • • • • • •

Light intensity Light dimming control Light spectrum control AC control Heating control Room pressure control Fan control Irrigation control CO2 controls

Remember, “The only thing the same about every grow is they are all different”

Once you determine your wants vs. must-haves, you can investigate what control system will offer the best options for you. Things you should consider are open-source software/equipment, ability to export data, remote access via the internet, ability to send offsite alarms, ability to custom program schedules, CFR21 Part 11 compliance (GMP buildings), etc. At Stratus, we are an authorized Reliable controls dealer, so most of my control background is directed from being part of their dealer network. I will use Reliable as an example of a company that integrates with most sensors, open-source controls protocols, and practically unlimited flexibility. For a typical facility, we look at controlling just about everything from a single online or local graphical source so the operator(s) of the facility can monitor and control everything in the building from one place. We allow access for scheduling of lighting, changing daytime/nighttime temperature/RH setpoints, text message or email alarms for space conditions, and more. All these individual items provide you with peace of mind and the ability to monitor your system from anywhere in the world you have internet and cell service. The ability to customise each grow is critical, and without the customization, a perfect environment will be challenging. Remember, “The only thing the same about every grow is they are all different .” If you are installing environmental controls, make sure the installer does what you are looking for and doesn’t just give you a generic system. Ensure

VENTILATION & DEHUMIDIFICATION

you get complete handover documentation saying all the different sensors in the building, how they are wired together, where to buy spares, who to call for troubleshooting etc. These are all things you will need; it is just a matter of time. Also, consider having a service contract with your controls company, as it typically takes an entire year to dial in an environmental control system.

Once you determine your wants vs. musthaves, you can investigate what control system will offer the best options for you

Fixing Issues Before They Happen Sunrise and sunset your lights Plants in nature see a sunrise and sunset. We take from nature and use it to help control the environment of the plants. By doing a sunrise, we can tell the air conditioning, dehumidification, and humidification that the room is about to heat up. We also know that our RH naturally will drop as we heat our environment. Remember, RH is relative to temperature. If you increase your room temperature without adding moisture, the RH will drop, but the moisture content of the room stays the same. The control system can look at the RH in the space and know it will drop from past records, and in turn, it can decide in advance to turn on the humidifier so you can stabilise RH during sunrise. For sunset, do the opposite. Most people flip the switch, and the lights go out. By doing this, you lose all the heat generated by the lights in an instant, and if your air conditioning is running, then you can be sure you’ll over-cool the space. Overcooling the area will not only cool the room but cause your RH to spike. Sunset your lights over 30 minutes to better predict the environmental change and ramp the dehumidifier, air conditioning, and heating all at once to stop the RH spike. Removing the RH spike will help drastically with things like PM. Predicting moisture loads being added to the space If the automation system in the building can also seamlessly integrate the irrigation, then the controls can tell when water is entering the area. As we now know water is coming, we can predict the need for dehumidification and try to stop an RH spike from occurring. Equipment maintenance intervals In general, when we design buildings, we do our best to control each item individually. So, for example, if we had five small air conditioners in a room, we control each one separately and make sure annual maintenance isn’t needed on each unit at the same time. In addition, we can run a lead/leg approach, meaning we can artificially keep the run hours of equipment different, so you don’t have big bills all at once or the risk of equipment failure happening simultaneously. CO2 Control Typically, liquid CO2 control is done using a solenoid on a liquid CO2 line. We see many people command the valve just on or off

Drying room

and wait for the CO2 to hit the desired level. Often, CO2 overshoots in the space. We suggest using a pulse-style approach, only opening or closing your value for brief increments and then looking at the room sample readings. In general, the CO2 sensor(s) in the space takes a little bit to respond as the CO2 needs to diffuse evenly in the space. With this control style, you can save money by using less CO2 and also fix the spikes in CO2 that many facilities see.

Low Cost vs Expensive HVAC There aren’t many options for cost-effective HVAC for the average home grower. However, some neat systems are available to make low-cost systems perform better. If I were doing a lowcost home grow setup, I would use whichever brand low-cost “mini-split” your friendly refrigeration mechanic can access. The neat thing about mini splits is regardless of the name brand, there aren’t that many factories in the world. So I look to companies like Intesis, which builds open-source IR controls modules (among other things) that control just about any mini-split on the market. You can use this little device to take your remote control on the road with you and monitor the current temperature conditions in your grow. You can also schedule increments to help stop the RH spike going into nighttime, cooling just as the lights turn on. With a small room and an off-the-shelf residential dehumidifier, you should be able to get decent enough control to grow some good quality product.

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VENTILATION & DEHUMIDIFICATION

What if the air conditioning and dehumidification know there will be a demand for heat before the lights turn on? What if your dehumidifier knew you were about to water the plants or foliar spray?

As you become a more sophisticated grower, be aware that there is a lot of equipment that I have never been convinced is worth the upgrade. You get more capacity. However, you don’t necessarily get all the benefits compared to the cost. When people install “commercial 5-ton” units, it is difficult to control the spikes. It is easier to manage five 3-ton mini-splits than three 5-ton air handlers in a room. I recommend avoiding this middle space, as, by the time you automate everything to work just right, you may have been cheaper going with the top-of-the-line air handling unit.

For growers striving for top-quality plants, dedicate an air handler (or multiples depending on your redundancy requirements) to each grow space. When I design an air handler, I always use semi-custom units. Many items are essential when selecting a top-quality HVAC unit, including: • • • • • • • • •

proper filtration fresh air/exhaust capabilities built-in dehumidification independent cooling/heating solid interior liners (no exposed insulation) all uncleanable equipment out of the air stream integration with building automation system gas or propane heat MERV 13(at minimum) post filtration

Chilled Water vs Direct Expansion When it comes to cooling, there are two choices: direct expansion refrigeration or chilled water. If you go with direct expansion, it is typically to save upfront capital costs. Direct expansion means each air handler has its compressors and refrigerant charge. The single biggest issue with direct expansion in each air handler is making sure you have enough capacity control on your cooling coil to stage your dehumidification. I recommend digital compressors to accomplish this goal. Typically, this will let you modulate to at least 10:1 of your nominal compressor capacity. Assuming they have the capital, my preference for clients is a chilled water system. Chilled water allows us to control capacity from essentially no cooling to full cooling. We can modulate the cooling flow, and from that, we can control a very tight temperature and RH in the space. The detriment to chilled water is it essentially always costs more upfront to install. The benefit, however, is better environmental conditions and a much lower long-term operating cost.

Air Distribution

One area of a grow room that is often done very differently by all growers is air distribution in the space. Some growers dump all the air in one end, remove it from the other, and add lots of fans for turbulence. Others avoid having extra fans in the space. With a ducted system, the general approach I usually take is a uniform distribution in the space, aiming to get the air from the diffuser to mix with the room. To accomplish this, we use “radial twist diffusers .”A radial twist diffuser is designed to spin the air as it enters the room to cause turbulence and mixing in the space. This is an excellent way for ducted systems to avoid extra fans in the space. If you go this route on mini-splits, it will be tough, if not impossible, to achieve the designed breeze on the plants. From a returning air to the air handler perspective, there is a cost-effective way and the best way. The absolute best placement for return ducts is floor-mounted hidden in your walls, which allows for all the cold air to enter high, get heated by the lights, pick up the moisture, pick up the dust particles and then “sweep” all the air through the floor grill. This gives the best environment, but at a very high cost. The common compromise is to use a single low return at the back of the room. However, that creates a small microclimate at the front of the room. My least favourite way is doing a distributed overhead top return; I don’t believe enough air mixes within the canopy and often short cycles.

Summary on HVAC and Environmental Controls/Monitoring All growing facilities are unique. Determining growing goals and budget is essential. We can reach for the stars with incredible air handling and controls designs, or we can grow organic on a budget. To get the perfect plant, you need the perfect environment. 3

Bio

Adam has provided planning and design services for cannabis and hemp cultivation and processing facilities over the last seven years with Stratus. His projects involve outdoor cultivation, indoor cultivation, drying, processing, extraction, storage, bottling and packaging, and more. Living on a hobby farm, Adam loves all plants, including flowers, vegetables, and microgreens, but is most passionate about hemp and is in awe of the fast-growing plant and all of the benefits it offers to humans and the environment alike.

BY CATHERINE SHERRIFFS

From Film Sets

To Patios, Victory Garden LA Rewrites The Script

hypohe saying goes that when one door closes, another opens, and Los Angeles-based commercial chlorous acid Raul Fernandez can vouch for that. When the global pandemic called Cut! on his director

career in March of 2020, Fernandez was left with a lot of time on his hands. So looking for

things to do, he built his wife two raised garden beds and posted some pictures on Instagram. Little did he know he was about to launch a second career.

VICTORY GARDEN LA

looking for things to do, he built his wife two raised garden beds and posted some pictures on Instagram. Little did he know he was about to launch a second career

“Someone suggested I sell them, and after a post on NextDoor, everything suddenly changed,” explains Fernandez. “I was almost immediately overwhelmed with orders.”

Los Angeles-based commercial director Raul Fernande in his workshop

It was the perfect storm; a worldwide lockdown in spring had created a sense of urgency for sustainable living. People everywhere suddenly wanted to become gardeners and grow their own food and flowers. It’s the ultimate hobby that not only fills time but brings beauty and resilience to yards and balconies everywhere, and people were taking notice. With demand for his planters skyrocketing, Fernandez hired his neighbour to cut the wood in his driveway while he assembled the product on his patio. The orders kept rolling in, and before long, he realised he had a booming business on his hands and needed more space and people. He partnered with his friend and producer, Colin Hakes, and Victory Garden LA was born. They hired fellow film industry types who were also out of work and finally set up shop in Boyle Heights, building and delivering planters to the greater Los Angeles area. Their company specialises in making raised garden beds, but they do much more than that. They’ve designed irrigation systems that seamlessly integrate with the planters and easily connect with standard garden hoses; nothing too complicated! The team also makes incredible critter covers to keep animals out, birdhouses, and trellises to support climbing plants. Victory Garden LA prides itself on being a one-stop shop, selling organic soil from a local composting facility. Customers love that their garden beds come ready to use with healthy soil; all they need after that are some seeds or seedlings. It’s been a lot of work, but Fernadez views starting up his company as one of his life’s greatest opportunities and experiences. Looking back at the early days, he’s proud of the positive vibes he created during challenging times. “Especially in the beginning, people were so psyched to even have some quick human interaction when we did drop-offs. People get really happy when their garden beds arrive; it quickly becomes a slice of backyard therapy,” he says. “We hear a lot of stories from older people that said they had given up on growing their own food because the physical work involved was just too much for them. Because we offer the taller legged options, everyone can easily access their plants [...] We try to lower the barrier for entry and make urban gardening accessible to everybody, regardless of knowledge or physical ability.”

VICTORY GARDEN LA

It was the per fect storm; a worldwide lockdown in spring had created a sense of urgency for sustainable living As pandemic restrictions lifted and film sets across California began opening up again, many of Victory Garden LA’s employees got back to their old jobs again, including Fernandez himself. But the obsession with gardening isn’t dying down, and so Fernandez juggles both of his careers as best he can. His wife is passionate about urban farming and has taken over a lot of the managing work, and Fernandez pops by the shop once or twice a week to see how things are going. He still employs a rotating cast of people in addition to two full-timers. “It’s nice to think about the hundreds of people we have been able to introduce into gardening and offer some light relief in these past few years,” Fernandez says. “Most of all, though, I love being able to employ people in well-paying, enjoyable work. It’s amazing to think that this little thing that started in my patio so quickly was able to provide jobs for dozens of people.” As we emerge from various lockdowns, it’s possible to envision a life without COVID-19 restrictions but impossible to imagine one without gardening. The grow your own movement is about more than food and flowers; it’s about passion, creating outlets, and building communities and a sense of self. Victory Garden LA embodies all of those things. Learn more: victorygardenla.com victorygardenla

BIO Catherine is a Canadian award-winning journalist who

worked as a reporter and news anchor in Montreal’s radio and television scene for 10 years. A graduate of Concordia University, she left the hustle and bustle of the business after starting a family. Now, she’s the editor and a writer for Garden Culture Magazine while also enjoying being a mom to her three young kids. Her interests include great food, gardening, fitness, animals, and anything outdoors.

BY CATHERINE SHERRIFFS

WAYS To Jumpstart The Growing Season By now, we hope you have a good grasp of the ins and outs of lighting and ventilation in the indoor garden. Although complex, understanding how all of these elements work together can lead to tremendous results! But the garden doesn’t have to be complicated; there are some simple, low-tech ways to help your plants take full advantage of the sunlight in cooler seasons. Without further ado, here’s our list of 5 Cool Ways to jumpstart your growing season!

Greenhouses, Cold Frames, and Row Covers

et/ denandgreenhouse.n credit: https://www.gar

A personal greenhouse goes a long way in getting a headstart in the garden.With glass walls and ceilings, the free heat certainly gives plants the boost they need and allows for outdoor growing well before your region’s last frost date. At night, heating systems can help keep the greenhouse warm. Not in the market for such a large structure? Cold frames are a fantastic alternative and don’t take up too much real estate! These beauties are bottomless gardens with transparent tops (think repurposed windows) that take in the sun’s rays during the day and release that warmth throughout the night. Cold frames are inexpensive and easy to build; a quick online search will offer plenty of easy DIY guides. Finally, using transparent plastic or horticultural fleece, row covers will also help protect delicate crops from the cold, wind, and other nasty elements.

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Create Microclimates

Want to trick your plants into thinking it’s warmer outside than it is? You can easily create microclimates to help extend your season, and it doesn’t have to cost a fortune, either! For example, filling plastic milk containers with water and placing them near your beloved crops creates a thermal mass. The jugs trap the heat from the sun during the day and release it at night when temperatures dip. The same goes for dark plastic sheeting, which attracts the sun and keeps the soil underneath nice and toasty. Not a fan of plastic lying around the yard? You’ll get the same result by planting crops near rock walls, which also trap the warmth from the sun while looking pretty too! Straw bales are also an excellent natural insulator; place them around your garden for a little extra heat and to protect plants against the elements. When the bales start breaking apart, they can work overtime by serving as mulch, which is essential to reducing water evapouration and soil erosion in the garden.

GREEN ADVICE

Cloches

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When it comes to crops like beets, broccoli, chard, and kale, you can get your growing groove on earlier than your season’s last frost date with the help of plastic or glass cloches.These cute little bell-like covers sit neatly overtop delicate plants in containers or on the ground. Much like row covers and cold frames, cloches absorb and trap heat from the sun and protect against spring frosts. However, they’re a little more versatile in the sense that you can quickly move cloches around to various spots of the garden throughout the growing season. You can purchase plastic cloches from a nursery or make them yourself using old water bottles. Be sure they have proper ventilation, as cloches tend to trap a lot of moisture, leading to powdery mildew problems.

Garden Heating Cables

If you like clear sightlines and structures aren’t your thing, you can still help boost the soil’s warmth with garden heating cables. Heating cables come in different lengths and are insulated and plastic-coated so you can bury them without worrying about the cold and moisture. In addition, you can choose to use a thermostat so that the cables turn off on warm days and maintain the desired temperature when things cool down. Installing them is pretty easy; be sure to follow all safety guidelines, including having proper electrical outlets and even placing a wire mesh overtop the cables to protect them from garden shovels and spades.These babies will work even better if used with a hoop house, greenhouse, or cold frame.

Indoor Gardens

We’d be remiss if we didn’t really go back to the basics and mention indoor gardening as a great way to get growing sooner.This edition offers plenty of advice on doing exactly that; we hope you’ve gained a wealth of knowledge when it comes to lighting and ventilating your indoor space. But keep in mind that nothing has to be complicated; growing indoors can be as simple as purchasing some inexpensive grow lights, heat mats, and upcycling some old yoghurt cups as seed starting pots.You have total control over your indoor garden and can jumpstart your outdoor growing season in the comfort of your home!

Source: Four-Season Food Gardening: How to grow vegetables, fruits, and herbs year-round, by Misilla Dela Llana (Quarto Publishing Group, 2022).

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BY PHILIP MCINTOSH

Tissue Culture I I

s m o o r h Mus Plants are perhaps easier to grow and maintain in the lab than either fungi or animals, but concerning tissue culture, the mushroom-producing fungi are the easiest to work with by far

t should come as no surprise that it is possible to multiply and grow organisms from across the kingdoms of life directly from their tissues, including plants, fungi, and animals. Animals present the biggest challenge, followed by plants. Plants are perhaps easier to grow and

maintain in the lab than either fungi or animals, but concerning tissue culture, the mushroomproducing fungi are the easiest to work with by far. The growth media are easy to make, no hormones are required, and most fungi will grow well vegetatively over a fairly wide temperature range. Producing mushrooms requires additional work, but obtaining and maintaining starting material in axenic (uncontaminated) culture is a necessary first step.

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TISSUE CULTURE

The fungal kingdom is diverse, but we will focus on basidiomycete fungi that reproduce by generating spores in mushrooms with gilled caps. Pretty much any of the common edible species such as Agaricus bisporis (button mushroom, crimini, portabella), Pleurotus ostreatus (oyster), Lentinula edodes (shiitake) and many others can be cultured from the fruit bodies—the mushrooms themselves.

If the agar is poured hot, it will create a lot of condensation in the plates, increasing the chance of contamination later on, so let the agar cool to close to its gelling point before pouring. There should be enough for about 6-10 dishes poured fairly deep. Deep plates will not dry out as fast as shallow ones. Once the agar sets, these plates are ready for use or stored in a refrigerator wrapped in plastic.

Sourcing Mushrooms

PDA Recipe Much of the equipment needed for growing mushrooms is the same for plant tissue culture (see sidebar). A variety of media will support fungal growth, but one of the easiest to make and most effective is potato-dextrose-agar (PDA). You can buy ready-to-make PDA in powder form (or even media already in Petri dishes), but most fungi will grow better on home-made. Here’s one way to make PDA: Shred 100 g of raw potato and boil in 600 mL of water for at least one-half hour. 2. Let cool and strain through a fine sieve to remove solids. 3. Add the extract to a graduated cylinder and make up the volume to 500 mL. Transfer to a 1000 mL flask. 4. Add 5 g dextrose (glucose) and 9 g of agar agar (gelling agent) to this potato broth. 5. If desired, add 0.1-0.5 g of peptone or yeast extract (or both). 6. Stir well and adjust the pH to 5.8. 7. Heat the mixture on a hot plate or carefully in a microwave oven (do not boil over) to dissolve the agar and other ingredients. 8. Transfer the well-mixed medium to smaller Erlenmeyer flasks (no more than half full, with loose tops) and autoclave (pressure cook) at 121°C for 15-20 minutes. 9. Do not vent the pressure vessel; let it gradually return to atmospheric pressure. 10. When the medium has cooled to just before its gelling point, quickly pour into Petri dishes using sterile technique (for example, keep the lid above the open dish while pouring to protect it from contamination from above). Fill each Petri dish half full or a bit less.

Now you need a mushroom. Experienced mycophiles will find and recognise possible candidates in their forays in the woods and fields. Since discussing the identification of wild edible species is beyond the scope of this article, we will assume you have a mushroom in hand that you wish to propagate. For training and educational purposes, you can try store-bought mushrooms but be advised that intellectual property agreements and related restrictions may prohibit the reproduction of commercial strains.

Figure 1

Commercial button mushroom

We begin with the humble button mushroom (Figure 1). First, select a mushroom as young and fresh as possible with no signs of decay. Work in a HEPA filtered laminar flow hood if available. Otherwise, work quickly and keep the mushroom tissue and the agar surface exposed for as short as possible. Here is a step-by-step procedure: 1. 2.

6. 7.

Wipe down all work surfaces, disinfect all tools with 70% isopropanol, and have several PDA plates nearby. Wear rubber gloves (nitrile preferred) and wash gloved hands with 70% isopropanol. No short sleeves! YOU are usually the biggest source of contamination. Use an X-ACTO knife or a scalpel to make a small slit in the side of a selected whole mushroom cap. Sometimes it works better if you make the slit in the stem’s bottom. With the slit as a starting point, gently tear the mushroom in two halves, place both halves in a Petri dish, and cover with the lid (Figure 2). Remove the lid from the covered mushrooms and, using a sterilised X-ACTO knife or scalpel, cut a small piece of tissue from the centre of one side of the cap. Choose a location that is as far away as possible from the outer surface of the mushroom. Figure 3 shows a mushroom that has been sampled. Keep the tissue sample on the end of the cutting tool and replace the lid over the mushroom. With one hand, lift the lid off of a PDA plate (but keep the lid hovering over the agar surface for protection) and transfer the tissue sample from the tool to the centre of the agar surface and quickly replace the lid. A larger tissue sample will have a better chance of getting going than a small one.

Figure 2

Mushroom split in two halves, and both halves placed in a Petri dish

Figure 3

Split mushroom cap showing locations of excised tissue

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TISSUE CULTURE

Figure 4

Mushroom tissue sample on agar medium

Figure 5

Successful mushroom tissue culture with minimal contamination, shiitake in this case, on commercial PDA medium

For training and educational purposes, you can try store-bought mushrooms but be advised that intellectual property agreements and related restrictions may prohibit the reproduction of commercial strains

Inspection is Critical Repeat the process several times to increase the chance that at least one of the plates will produce a contaminant-free mycelium (mycelium = colony of filamentous fungus). Incubate the cultures in the dark at room temperature. Inspect the cultures every day and discard any that have bacteria or mould on them. Mushroom hyphae (the slender thread-like cells of the filamentous fungi) produce a fuzzy white colony emanating directly from the tissue sample. Moulds tend to grow faster and will produce coloured spores. Look for a solid bit of pure white fungal growth on the sample, and after a few days, it will expand onto the PDA surface. Sometimes the mushroom mycelium will grow but also be contaminated. In this case, it is often possible to subculture the fungus until a pure culture is obtained. If there is little or no contamination, but nothing grows, the mushrooms are too old, and you need better starting material.

Mushroom Tissue Culture Supplies List • • • • • • • • • • • • • • •

pressure cooker/canner Petri dishes Erlenmeyer flasks with caps or stoppers (250, 500 mL) graduated cylinders (100, 500, 1000 mL) precision balance (0.1 g resolution or better) pH meter potatoes agar agar dextrose (glucose) yeast extract and/or peptone (optional) scalpel or X-ACTO knife 70% isopropyl alcohol nitrile gloves cheesecloth or fine mesh filter bag alcohol lamp (optional)

Culture Time Mushroom mycelium can be refrigerated on plastic or Parafilm® wrapped Petri dish for several months without losing vitality. Figure 4 shows a PDA plate with a small bit of tissue taken from a button mushroom. Figure 5 shows a culture becoming established. Once you have a pure culture, you can keep it going indefinitely by serial transfers to a fresh medium. There is a lot to growing a successful crop of mushrooms, but a big part of success is starting with uncontaminated material, and that is what you’ll have once you master these techniques.

Bio

Philip McIntosh holds a B.Sc. in Botany and Chemistry from Texas State University and an MA in Biological Science from the University of Texas at Austin. He has been publishing professionally for over 30 years in magazines, journals, and on the web on topics relating to botany, mycology, general biology, and technology. As a STEM (Science,Technology, Engineering, and Math) educator, Phil enjoys working with students to help them advance their knowledge and skills in relevant fields of learning.

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CHEERS TO A LEGENDARY SEASON!

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