Maximum Yield UK Sept/Oct 2011

UK September - October 2011

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Maximum Yield UK | September/ October 2011

CONTENTS september / october 2011 FEATURES 24

20

Cool Toys and Tools for High-tech Growers

24

Top 6 Greenhouse Gardening Tips

28

Plant Propagation: Discovering Rooting Hormones

34

The Cost of Sunlight

38

Chelated Micronutrients

by Dr. Lynette Morgan

by Gary Pearson

by Matt LeBannister

by Ed Harwood

by Donald Lester

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DEPARTMENTS 28

6

From the Editor

6

Letters to the Editor

8

MaximumYield.com

10

Simon Says

12

MAX Facts

16

Product Spotlight

44

You Tell Us

46

Talking Shop

49

Do You Know?

49

Coming up in November/December

50

Max Mart

38 Maximum Yield UK | September / October 2011

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FROM THE editor

jessica raymond

Autumn signifies transition, a new season and a chance to modify and improve your current garden or to delve into a new one.This September/October issue gives you all the tools to do so with some of our best articles, the latest growing information and how-to tips on chelated micronutrients, cool hydro toys, greenhouse gardening, plant propagation and more.

Looking for new products to help your garden grow? Look no further than the Product Spotlight on page 16. From lighting emitting plasmas and propagators to mufflers, nutrition and organics, the latest innovations our industry has to offer are sure to get you excited about the new indoor growing season.

Thank you to all of our UK readers, retailers and exhibitors that made it out to California this past July for the 8th Annual San Francisco Indoor Gardening Expo. It was by far our biggest and best show to date. Looking ahead, we invite you all to attend the upcoming 2nd Annual Long Beach Expo, October 23, 2011.You can expect over 275 booths touting the latest innovations and earth friendly grow gear, live demonstrations, education seminars and door prizes throughout the weekend.Visit www.indoorgardeningexpo.com to learn more about this and our 2012 Expo line-up. See you at the show!

Jessica Raymond, Editor editor@maximumyield.com

letters to the editor Reader Props

You have a great looking magazine—sharp bright colours, good quality paper and covers. I look forward to reading every issue cover to cover in my ever expanding quest for more hydroponic/ indoor growing information. I find the articles current and interesting and I find Simon Says great. Overall, much better than other similar magazines.

Ron Daily

Loving Out Loud I love your mag.

Jose Garza Love your magazine and online info.

Sharon Calabrese I would love a subscription to your wonderful magazine. I get it whenever I can but the store runs out fast and I miss issues. I love how up-to-date it keeps me with new products.

Cody Eurich Maximum Yield has compiled one of the most extensive sources for technical information I have seen.

Bob Wheeler I love your magazine and I read it all the time.

Ricardo Your article on light sources, amount of time and heat was very informative.

Julie Brothers

Thanks.We love you too! Keeping growing and keep reading Maximum Yield.We appreciate all your comments.

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Maximum Yield UK | September/ October 2011

Yellow and Mellow In the March/April 2011 issue of Maximum Yield UK, I was happy to see Matt LeBannister’s article on dealing with yellowing leaves. Yellow leaves are a recurring problem in my crops. I was wondering if a nitrogen deficiency could be the problem in yellowing bamboo stalks as well. In an older online article from Therese Cressman (Growing Guide: Lucky Bamboo) she says yellowing leaves are a sign of too much light or too much fertilizer. She recommends removing the yellow leaves right away. I did but my bamboo continued to suffer. Any suggestions to help my bamboo are much appreciated.

Ruth Alston

If the leaves on the lower part of the plant are the ones that are yellowing it is likely to be a nitrogen deficiency.With bamboo it could be caused by fluctuating pH levels. Using pH drops to check the water before it is replaced might do the trick.

Bamboo is often grown in containers that cannot be drained.

I would recommend replacing the growing container and medium to rid the root-zone of built up nutrients that cannot be flushed. Hope this helps.

MaximumYield Contributor: Matt LeBannister

We Want To Hear From You! Write Us At: Maximum Yield Publications Inc. 2339A Delinea Place, Nanaimo, BC Canada V9T 5L9 or editor@maximumyield.com

Maximum Yield UK | September / October 2011

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Coming up on the Web Upcoming Events

See, Learn, Discover and Grow at the 2011 Long Beach Indoor Gardening Expo Maximum Yield is proud to be hosting the 2nd Annual Long Beach Indoor Gardening Expo, October 23, 2011. See live demonstrations, learn at our information sessions, discover new techniques and delight in the uniquely diversified products that will help your garden grow. Visit www.indoorgardenexpo.com for full event details.

I N D O O R

G A R D E N I N G

VOLUME 11 – NUMBER 3 September/october 2011 Maximum Yield is published bi-monthly by Maximum Yield Publications Inc. 2339A Delinea Place, Nanaimo, BC V9T 5L9 Phone: 250.729.2677; Fax 250.729.2687 No part of this magazine may be reproduced without permission from the publisher.

If undeliverable please return to the address above.

The views expressed by columnists are a personal opinion and do not necessarily reflect those of Maximum Yield or the Editor.

Publication Agreement Number 40739092

Latest News Which city in Europe was deemed the green capital? Which restaurant in New York City features a fresh rooftop farm? What type of fish is perfect for aquaponics? Learn the answers to these questions and more on maximumyield.com under Latest News.

Got Questions? Get Answers.

Maximum Yield’s resident expert Simon Hart is available and ready to answer your modern gardening questions.

E-mail simon@maximumyield.com or fill out the Simon Says question form on maximumyield.com

PRESIDENT/PUBLISHER - Jim Jesson GENERAL MANAGER - Don Moores BUSINESS MANAGER - Linda Jesson EDITOR - Jessica Raymond jessica@maximumyield.com ADVERTISING SALES 250.729.2677 Linda Jesson - linda@maximumyield.com Lisa Lambersek - lisa@maximumyield.com Ilona Hawser - ilona@maximumyield.com Christina Indseth- christina@maximumyield.com Ashley Heppell - ashley@maximumyield.com PRODUCTION & DESIGN ads@ads.maximumyield.com Mike Linden - mike@maximumyield.com Jenn Duong - jennifer@maximumyield.com Tina Skujins - Tina@maximumyield.com ACCOUNTING - Tracy Greeno accounting@maximumyield.com

Connect to MaximumYield.com instantly from your Smartphone with our Quick Response (QR) Code, found on the cover of every issue of Maximum Yield. Now you can access the best products, the most indepth articles and information and the latest news, at high speeds. Simply download the QR Code Reader software compatible with your Smartphone, scan the QR Code and your phone’s browser will automatically launch, redirecting you to www.maximumyield.com. It’s that simple!

Connect with Maximum Yield

maximumyield.com • facebook.com/MaximumYield • indoorgardeningexpo.com • twitter.com/Max_Yield

Tell us what you think at editor@maximumyield.com. We’d love to hear from you.

contributors

Dr. Lynette Morgan holds a B. Hort.

Donald Lester is the plant

Tech. degree and a PhD in hydroponic greenhouse production from Massey University, New Zealand. Lynette is a partner with SUNTEC International Hydroponic Consultants and has authored five hydroponic technical books. Visit www.suntec.co.nz/ consultants.htm and www.suntec. co.nz/books.htm for more information.

products manager at JH Biotech, Inc., a California based agricultural technology company with 27 OMRI certified products. Donald has a master’s degree in agronomy with an emphasis in entomology. He is an agricultural scientist with over 10 years of research experience and 50 scientific publications to his credit.

Matt LeBannister developed a

Dr. Ed Harwood is founder and chief

green thumb as a child, having been born into a family of experienced gardeners. During his career, he has managed a hydroponic retail store and represented leading companies at the Indoor Gardening Expos. Matt has been writing articles for Maximum Yield since 2007. His articles are published around the world.

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Maximum Yield UK | September/ October 2011

executive officer of AeroFarms. Ed previously served as associate director of Cornell Cooperative Extension for Agriculture. Prior to that, Ed served as CEO of Topline Waikato, Inc.

UK DISTRIBUTION Growth Technology Future Harvest Developments Europe Nutriculture UK CANADIAN DISTRIBUTION Brite-Lite Group Biofloral Eddis Wholesale Greenstar Plant Products Inc. Hydrotek MegaWatt Northern Hydroponic Wholesale Quality Wholesale USA DISTRIBUTION Aurora Innovations BWGS General Hydroponics Humboldt Wholesale Hydrofarm Hydro International National Garden Wholesale / Sunlight Supply Nickel City Wholesale Garden Supply R & M Supply Tradewinds AUSTRALIAN DISTRIBUTION Dome Garden Supply Futchatec Growth Technology Holland Forge House N Garden Hydraspher

Maximum Yield UK | September / October 2011

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SIMON says

What have you heard about jellyfish fertilizer? I just saw a show produced in Japan about jellyfish fertilizer and I am wondering where I can buy some.

Would it be good for all stages of growth?

What a great question and a wonderful example of how ideas that experimenting in the garden can generate creative ideas. Before are being discussing the nutritional and efficacious nature of a jellyfish tested. Many fertilizer in the garden we should probably mention why this is people talk even being considered. about eating them, but the ones Jellyfish populations around the world are surging. Scientists people eat are actually endangered are pointing at global warming and environmental pollution. while the ones no one puts on a In areas where there is large agricultural runoff, nutrification table are exploding. of the water can cause anoxic (low oxygen) areas in the water.

In theory all things organic will Although this is very bad for fish, which tend to disappear, the decompose into organic matter and jellyfish seem to thrive with their ability to store oxygen within nutrients so jellyfish could become plant their physical structure—one of many exceptional evolutionary nutrients. Preliminary research has shown functions found within the lowly jellyfish. some positive results in field of vegetables.

Japan was concerned with their overpopulation and The initial research has been done in its effect on their fishing industry and tried to be Japan and the species of jellies they tested proactive. The government hired fishermen to drag razor have elevated levels of nitrogen and wire through the masses of jellyfish but it backfired phosphorous. They also have similar levels and unleashed a population explosion, a jelly survival of potassium, magnesium and calcium to mechanism when they are that “The only fish farm in Northern of the under attack, yet another evolutionary marvel.

Ireland was overrun by a flotilla of surrounding Overpopulation is a bit of an salt water. jellyfish 16 kilometres wide and 13 understatement in some cases.

Unfortunately In November 2007 the only they also have metres deep.” fish farm in Northern Ireland a strong level of was overrun by a flotilla of jellyfish 16 kilometres wide and 13 sodium and processes are being tested to try and reduce metres deep. The army of jellies ate through 2,000,000 worth of the sodium levels. fish and wiped out the farm before moving on.

With the issue of jellyfish overpopulation being international So we have a lot of jellyfish and we need to use them while I would think that if its found to be effective it won’t be long trying to limit their population explosion. There are many before it is an organic option for gardeners.

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Maximum Yield UK | September/ October 2011

MAX

facts

hydroponic news, tips and trivia from around the world

Real Food Festivals Deliver the Real Thing From Small Producers London’s Real Food Festivals are a chance to meet small, local, artisanal producers.

The Real Food Festival, held this past spring, featured over 400 hundred stalls and a full roster of chefs talking about their work.

In attendance was the Youth Food Movement, a community of young people working to raise awareness of “good, clean and fair” food for all. They offer a unified voice to promote the ideals of slow food and change the future of our food and farming.

Upcoming this fall are the Organic Food Festival and Real Food Harvest Festival.

(Source: www.treehugger.com, www.realfoodfestival.co.uk)

The Perfect Aquaponic Fish Aquaponics projects are cropping up all over the place, from Utah and Seattle in the United States, to Dalston, London and Annanside, Scotland. These projects utilize many different plants and fish although in recent times there seems to be a leader emerging from the pack of contenders. This fish is the tilapia.

Stockholm, Sweden: The European Green Capital Stockholm, Sweden has been deemed the green capital of Europe by the European Commission, receiving the award of the same name in 2010. This award promotes sustainable mobility and land use, modern waste management, eco-innovation and other green technologies.

By 2014, the city will become home to its first vertical farm, an immense urban greenhouse in the form of a geodesic dome designed by the Plantagon Company.

The glass sphere frees up the land mass needed for raising crops by maximizing square footage with its spiraling levels. Greenhouse plants are grown in a nutrient-rich solution using hydroponics.

In addition to its vertical farm solution, Stockholm is redefining urban planning to maximize an eco-friendly balance of life to address the crucial areas of population growth, water conservation, renewable energy and rising food costs. The city has also begun taking steps toward adding new sources of renewable energy to power their commercial needs.

(Source: www.theurbn.com)

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Maximum Yield UK | September/ October 2011

Tilapia Facts: • A cichlid fish found widely in freshwater around the world • The third most important species in fish farming behind salmonids and carp • They grow quickly, breed easily and are exceptionally hardy • Referred to as “aquatic chicken” • The US now consumes a whopping 475 million pounds of tilapia in 2010, four times the amount 10 years ago It is certainly a worthwhile fish for a wide variety of aquaponics projects, from large scale agriculture to small scale home-based systems; whether tilapia and chips will ever replace cod and chips, however, remains questionable.

(Source: http://hydroponicsguide.co.uk)

Maximum Yield UK | September / October 2011

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MAX

facts

hydroponic news, tips and trivia from around the world

DNA Reveals Origins of First European Farmers

Going Green - China Show Us How

A team of international researchers led by ancient DNA experts from the University of Adelaide has resolved the longstanding issue of the origins of the people who introduced farming to Europe some 8,000 years ago.

A detailed genetic study of one of the first farming communities in Europe reveals marked similarities with populations living in the Ancient Near East (modern-day Turkey, Iraq and other countries) rather than those from Europe.

The ancient DNA used in this study comes from a complete graveyard of Early Neolithic farmers unearthed at the town of Derenburg in Saxony-Anhalt, central Germany.

More than 5,000 visitors attended the Eco Design Fair in Shanghai this past spring. Visitors were presented with a glance of Shanghai’s most creative products and design in the realm of environmentally-friendly consumer goods available in China.

Seminars focusing on how to create sustainable businesses, lessons in urban farming and even hydroponics, were all available for the public to learn about simple ways to help the environment.

(Sources: www.ecofriendlypack.com, www.theurbn.com)

(Source: www.sciencedaily.com)

Europe’s Wildlife Under Threat from Nitrogen A new international study warns that nitrogen pollution, resulting from industry and agriculture, is putting Europe’s wildlife at risk. More than 60 per cent of the EU’s most important wildlife sites receive aerial nitrogen pollution inputs above sustainable levels.

(Source: www.sciencedaily.com)

Nuts About Hydro The Greenearth Project in Savusavu, Fiji has constructed an ingenious hydroponic growing system of bamboo and coconuts. The system uses coconut husks (coir) as a growing media, and worm castings and humus tea as fertilizer.

(Source: www.fijilettuce.com)

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Maximum Yield UK | September/ October 2011

Free Tomato Giveaway to Get Growing The Mayor of London was in Trafalgar Square giving away free tomato plants as part of Capital Growth, a scheme to get Londoners growing fruits and vegetables. Their aim is to create new community food growing spaces across London by the end of 2012.

Capital Growth is working with four different communities on creating allotment gardens and communityled food growing projects in very urban areas where land is at a premium.

In support of this particular tomato initiative, B & Q donated the plants. Last year they sold 214,000 tomato packs of seeds and 250,000 tomato plants, making tomatoes one of their most popular fruits to grow.

(Source: www.treehugger.com)

Student-Organized Farmers Markets in Schools UK-based organic farming charity the Soil Association is initiating the creation of school-based farmers markets. From the natural sense of community that builds around a school, to the physical infrastructure, to the educational opportunities of allowing kids to organize and run their own farmers markets and learn about local foods, there are plenty of healthy synergies going on here. Add to that the income that can be used by schools to fund sustainability programs, and the new markets this provides for local growers, and it’s hard to see how anyone could fault a program like this.

(Source: www.treehugger.com)

Maximum Yield UK | September / October 2011

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PRODUCT spotlight

Ask for them at your local indoor gardening store.

YOUR GUIDE TO THIS ISSUE’S HOTTEST ITEMS

Phat Filters Genuine Phat Filters use state-of-the-art design with the best odour absorbing carbon found in the world to give you the best clean-air-producing, greenhouse filter on the market. Phat Filters are made with 1,200 milligrams per gram iodine number, virgin charcoal and a higher grade charcoal than our competitors. Aluminium construction, lightweight charcoal carbon and an anti-air bypass ensure proper filtration. A new internal mesh material eliminates shipping dust plus our new internal packaging ensures safer transport and a conical bottom-air diverter ensures even airflow. All these reasons and more make Genuine Phat Filters the best choice on the market. Available now at your local hydro shop. Phat is a registered mark of International Growers Supply.

Flo-Gro 500: The Ultimate Single Plant System For growers looking to cultivate mother plants, take a look at the Flo-Gro 500. A drip ring feeds the roots from above and gravity pulls the nutrient solution down, oxygenating the root zone as it drains for increased nutrient uptake. Variable feedings set on a timer means growers can set an optimum feeding schedule for their environment.

Plants take up far more nutrients and water than they would with hand watering. Any nutrients not used drain back into the reservoir, instead of building up at the bottom of the planter. The Flo-Gro 500 also ensures no nutrient buildup and increases oxygen to the root zone. Check it out at your favourite hydroponics shop.

New Packaging, New Possibilities From Plagron As your partner for better growth, bloom and yield, Plagron is introducing new packaging.

As of December our new, fresh packaging will be featured on our entire product line in grow shops around Europe. The whole operation consisted of over 100 facings in five product categories: Bio, Terra, Coco, Hydro and Plagron’s additives line Universal. In design as well as composition, the total assortment will help growers get better results. The information and instructions on the packaging is more structured and easier to understand. Plagron wants to be the brand that growers use and consult to get the best possible yields. Visit your local hydroponics shop to check it out.

Gavita Pro 300 LEP The Gavita Pro 300 LEP (light emitting plasma) is a solid state horticultural plasma light fixture. There are no moving parts in the fully sealed housing, improving the reliability. The light source is a Luxim LiFi-STA-41-02 module that has a rated average life of 30,000 hours. The glass wide spectrum filter allows for low quantities of UVB light to pass while shielding you and your crop from UVC. The miro aluminium reflector generates an even square light pattern. The absence of heat radiation in the light allows you to hang the lamp close to your crop, or to add the light without adding extra heat radiation to your crop. Talk to your local retailer for more information about the Gavita Pro 300.

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Maximum Yield UK | September/ October 2011

Introducing General Organics - Now Available in Europe General Organics (GO) is a complete line of superior plant foods and supplements that enable you to enrich your garden and the planet. They combine time-tested materials with the ecological and efficient methods of the future. The line represents General Hydroponics Europe’s deep commitment to sustainability, quality, simplicity and innovation.

GO includes our current certified organic fertilizers as well as new additions that work in synergy at different levels of a plant’s physiology. All of the products in the GO line improve plants’ health and their resistance to sickness, and increase flowering and fruiting quantities and quality.

The GO line is a new concept that allows you to choose your preferred supplements and mix them according to your needs. The feeding charts provided advise on the best combinations for mixing and matching, but the GO product line is your playground where you create your own experiences and your best personal formulas. Check out General Organics at your local hydroponic/organic gardening shop.

Gavita Pro 1,000 The Gavita Pro 1,000 is the first 240 volt electronic ballast that powers the professional Philips GreenPower 1,000 watt 400 volt electronic double ended lamp. This lamp has the highest PAR light output, improved spectrum and the best light maintenance of any horticultural lighting system. It is the only choice for Dutch professional greenhouse growers. The Gavita Pro 1,000 is available as a complete fixture with the highly efficient professional HortiStar HR 96 1,000 DE reflector. Talk to your local retailer for more information about the Gavita Pro 300.

X-Stream Aeroponic Propagator 20 Site Unit The X-Stream Aeroponic Propagator 20 site unit from Nutriculture grows strong roots fast. Cuttings are ready to transplant in just 10 days. A constant supply of nutrient, water and oxygen, combined with the lack of restrictive growing medium, encourages roots to develop rapidly as they push out to access the nutrient solution for unrestricted root development. Heat and humidity are fully controllable by gradually opening the large but ter fly vents in the X-Stream humidity lid.

Cuttings are placed in mesh pots using neoprene collars and the pots are suspended inside a misting chamber for a sterile root zone and lower risk of disease. For more information visit an indoor gardening shop near you.

Organic Air Charcoal Fiber and HEPA Filters Organic Air Charcoal Fiber and HEPA Filters are lightweight, shippable, washable and perfectly suited for any greenhouse. Organic Air Charcoal Fiber Filters consist of high quality charcoal fiber mesh with zillions of micro-pores for optimal adsorption of nasty odours. Our HEPA intake filter keeps your grow room clean by filtering all moulds, spores, pollens, dirt and insects. The HEPA mesh is five times smaller than a human hair and works at all times with no oiling; a highly effective way to eliminate unwanted containments. Both filters are pleated for a doubling of surface area and utilize a dual inverted nose cone for maximal air flow. Available now at your local hydro shop.

Maximum Yield UK | September / October 2011

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PRODUCT spotlight

Your guide to this issue’s hottest items.

Boldtbags Suspension Kit The Boldtbags Suspension Kit is essential for easy bucket-less filtration using five, 20 or 32 gallon bag sets, as well as any Boldtbags patented Cone Kit. The Suspension Kit consists of military-grade nylon webbing and industrial strength nickel-plated snap clips, with reinforced stitching for guaranteed strength. The three foot webbing extensions simply connect to the grommets of any Boldtbag by way of the heavy-duty swivel snap clips, with a nine foot length of webbing to secure over your leverage of choice. The Boldtbags Suspension Kit is easy to use and makes filtration fun again. Whether your operation is large or small, the Boldtbags Suspension Kit doesn’t leave you holding the bag! Ask your local retailer for a Suspension Kit.

Phat Mufflers Phat Mufflers are made using an all aluminium body and a really phat glasspack that won’t disintegrate like foam over time. The noise reduction coefficient of our glasspack is 85 per cent versus 50 per cent for foam. Phat Mufflers are lightweight, durable and easy to hang, plus they’re available in four to 12 inches with mini sizes too for those tight spaces. Sold exclusively through Hydrogarden UK, Eltac Spain and Dutch Lighting Solutions Holland. Available now at indoor gardening shops across the UK.

Cannazym’s New and Enhanced Formula It has been almost two years since Canna introduced the new Cannazym formula. We increased the concentration of the enzymes, thereby increasing the activity of the enzyme on cellulose while decreasing the response interval for function. This simply means the formula is better for your plants.

Our latest Cannazym formula has an increased shelf life of 24 months. Plus, the product is now protected against extreme temperatures. Check out the new formula with a new look at your nearest hydroponic shop.

Boldtbags Five Gallon 8 Bag Kit The Boldtbags Five Gallon Eight Bag Kit gives you the ultimate range of filtration with the 220, 190, 160, 120, 90, 73, 45 and 25 micron bags and also includes a one inch squared pressing screen. Boldtbags are made from heat-fused nylon and FDA approved watertight lining, which ensures no liquid absorption and produces a higher yield. The Swiss grade mesh screens have been measured to the absolute micron and heat-stamped to prevent fluctuation. Boldtbags use reinforced military grade nylon stitching and are bolted at the stress points to keep everything in the bags and not on you. The durable nickel-plated grommets can be used easily with suspension systems and will never rust. Get your Five Gallon Eight Bag Kit today from your local hydroponics retailer.

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Maximum Yield UK | September/ October 2011

Gavita Pro 600 The Gavita Pro 600 is the first 240 volt electronic ballast that powers the professional Philips GreenPower 600 watt 400 volt EL (electronic lamp).

The Gavita Pro 600 is available as a complete fixture with the highly efficient professional HortiStar HR 96 reflector or as a remote ballast.

Being completely closed and solid state (no fans) with extremely low heat dissipation, the remote ballast can be mounted close to your lamps, reducing the amount of electromagnetic interference. Talk to your local retailer for more information about the Gavita Pro 600.

Introducing the X-Stream Heat Propagator From Nutriculture The X-Stream Heat Propagator offers ultimate heat control for large scale propagation. X-Stream Heat fits three trays of Grodan SBS cubes—that’s enough room for up to 450 seeds or cuttings. X-Stream Heat combines the heat and humidity retention of the X-Stream lid with an ultra accurate, thermostaticallycontrolled heated base. Temperature is fully adjustable from 5°C to 30°C, to within 1°C. Heat is dispersed evenly across the base; no hot or cold spots means plants develop at the same rate and can be transplanted together. A digital thermostat displays actual temperature and desired temperature for easy monitoring of the growing environment. For more information visit an indoor gardening shop near you.

Boldtbags Large Cone Four Bag Kit The Boldtbags Large Cone Four Bag Kit makes filtration easy and efficient with the 220, 160, 73 and 25 micron bags.

The micron screen continues up the bag and attaches to a metal ring at the top.

The bag is tapered from top to bottom creating optimum downward flow, as well as through the sides of the bag once product starts to collect at the base. The Large Cone tapers to a straight edge and can be inverted to produce a “brick” of extract or nutrients. The Large Cone can be used with a 32 gallon trash can, or used with a Boldtbags Suspension kit for bucket-less filtration. Ask your local retailer or get your Large Cone Four Bag Kit today.

Maximum Yield UK | September / October 2011

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Cool Toys and Tools

for High-tech Growers

by Dr. Lynette Morgan

Humans love gadgets. The widespread use of iPods, iPhones and Blackberries are testament to this so why should high-tech horticulture be any different? There is a wide range of exciting and useful tools, meters and instruments designed for horticultural applications that not only provide valuable, educational information but are also fun. While it may seem that high-tech grower gadgets are out of the budget range for many of us and only used for advanced research projects in university labs, in reality there are some toys and tools that won’t break the bank. Most of us know how to handle an EC or TDS meter and have a basic awareness of the range of methods used to measure pH on a small scale, but there are many more plant and environmental parameters that could be tested, quantified and adjusted to give even better plant performance. Tools exist to test and measure just about every plant variable from CO2, dissolved oxygen in the nutrient, surface temperature, sugar levels in plant material, individual elements in the nutrient solution, chlorophyll content of the foliage, PAR light, media moisture levels, peroxide levels, vapour pressure deficit, even entire plant photosynthesis, among others. There are also nutrient calculators and nutrient formulation software on the market for those who are into nutrient fine-tuning.

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Maximum Yield UK | September/ October 2011

photo by Spectrum Technologies

The IPM Scope – a hand held microscope and camera that links to a computer for full screen images.

IPM Scope – Digital IPM camera and hand held microscope This is a really great toy for checking the fine details of what’s happening at the plant level. Much of what goes on at the leaf surface is smaller than we can easily see and a whole other micro-world exists that is truly fascinating to view close up. This type of digital microscope is particularly useful for growers who have problems seeing the early signs of

“Microscopes are commonly used for magnifying small insects, plant diseases and other plant disorders.” pests and disease on leaf surfaces and for classroom hydroponics and science fair projects. Microscopes are commonly used for magnifying small insects, plant diseases and other plant disorders, however, this version goes one step further combining a digital movie camera, built-in LED lighting and precision options in a small hand-held microscope. This gives 40 to 140 times magnification so the fine details can be easily seen on a computer screen then captured as images or movies.

Pocket digital refractometer or brix meter Refractometers, also known as brix or total soluble solids meters, have been

“Brix is a reliable measure of fruit quality and flavour (sweetness) in many common hydroponic crops such as tomatoes, strawberries, capsicum and melons.” used in horticulture for many decades.

Hand held brix meters are most commonly used in the wine industry to determine when sugar levels in grapes are high enough to harvest. However, many other industries use refractometers to gauge crop maturity and food quality.

Brix meters can be one of the most useful tools for fruit and vegetable assessment if used correctly.

Refractometers range in cost, the most inexpensive being the older manual styles to the most expensive digital hand held refractometers that fit in your pocket and give a reading in seconds.

Brix is a reliable measure of fruit quality and flavour (sweetness) in many common hydroponic crops such as tomatoes, strawberries, capsicum and melons.

Commercial growers, in particular, should know how to use a refractometer. They should also know how the values of brix relate to fruit quality and flavour in their crops. The problem with the old manual brix meters has always been the scale, which needs to be read by eye;

Brix meters for measuring sugar levels in hydroponic fruits and vegetables are an essential tool for many growers.

Maximum Yield UK | September / October 2011

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Cool toys and tools for High-tech growers

it can be difficult to get a high degree of accuracy between samples that are relatively close in brix levels. The digital refractometer has an accuracy of 0.2 per cent and measures in increments of 0.1 per cent. For smaller growers brix meters are a highly useful tool where improvements in the growing system, cultivar or nutrition are being carried out to raise the quality of the crops being grown. Brix or sugar levels in many fruits and vegetables are also highly dependant on a number of factors such as light levels, EC, nutrition, cultivar, temperature and plant health.

Being able to measure brix from one crop to the next can give definitive evidence that plant quality is improving. It’s also interesting to measure the brix of different samples of tomatoes and other fruit and then see if taste tests can actually pick up on the same differences in sweetness.

Chlorophyll meters Chlorophyll meters are not necessarily standard hydroponic gadgets, but they can be fun, in some cases providing very valuable

Chlorophyll content of a crop’s foliage is a gauge of health and can be used as a disease diagnostic tool.

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information. Chlorophyll meters give an indication of plant health and stress before growth becomes adversely affected.Thus they are potentially a useful tool for hydroponic growers who would like to know if their

“Chlorophyll meters give an indication of plant health and stress before growth becomes adversely affected.”

plants are starting to suffer some stress long before potentially fatal symptoms—such as wilting—become more visible.There are a number of models of chlorophyll meters on the market, from simple versions to the high-tech, integrated data-logging models.

Chlorophyll content is instantly measured by clamping a sensor over a leaf and receiving an indexed chlorophyll content reading. Good quality, high-tech chlorophyll meters are not only a useful crop diagnostic tool, but also a great learning tool for classroom experiments and student projects.

Maximum Yield UK | September/ October 2011

Infrared thermometer Infrared thermometers are perhaps the simplest and often least expensive tools a small hydroponic grower can purchase. They provide particularly valuable data and can even determine when a plant has become stressed to the point where it has stopped transpiring. Infrared thermometers are also the easiest and straightforward of all the tools to use and they have extra uses around the home as well. Infrared thermometers are in widespread use in the food industry. They are used to non-destructively gauge food temperatures to ensure proper storage.

These gadgets operate by shining an infrared beam of light onto the surface of an object, or in the case of nutrient solutions, a liquid. The temperature of the surface of that object is then recorded and displayed in either Fahrenheit or Celsius on the meter’s digital display.

In hydroponics, this surface temperature reading is important for foliage.

The leaf or canopy temperature in a healthy plant usually differs from the air temperature and so should be checked, particularly under warm or high light conditions.

“The leaf or canopy temperature in a healthy plant usually differs from the air temperature and so should be checked, particularly under warm or high light conditions.”

Plants’ leaves transpire, cooling themselves in the process. A healthy, actively photosynthesizing crop will have a leaf temperature that is close to or slightly lower than that of the surrounding air. A crop that has become stressed and shut down with closed stomata will have a leaf temperature above that of the air temperature and eventually it will begin to wilt. Under these conditions the leaf is also not

photosynthesizing. The objective of measuring the leaf temperature with a non-destructive infrared thermometer is to assess plant stress and prevent plants from shutting down during the day due to heat, humidity or other disorders.

Infrared readings can also be taken of the nutrient solution at any point in a hydroponic system and are also great for checking solution temperatures in NFT channels, deep flow systems, aeroponics, raft systems or nutrient reservoirs.

Of course the list of tools, meters and gadgets designed for horticultural use is far more extensive than is covered here and there are some highly advanced systems for measurement of plant photosynthesis, individual nutrient elements and biomass production. However, in terms of small useful gadgets that can tell us something about our plant’s state of health, environment and productivity and allow decisions to be made that benefit growth, the five mentioned above are worth the investment. MY

An infrared thermometer can be used to determine if leaves are actively transpiring or have shut their stomata.

Maximum Yield UK | September / October 2011

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6

Top six

Greenhouse Gardening Tips

by Gary Pearson

In most ways greenhouse gardening is like regular gardening, except for a few things. You are accountable for checking on the environment and the plants growing in the greenhouse but the fundamental skills required are the same. Six important tips for greenhouse gardening have been suggested below to help an amateur greenhouse gardener.

1. Plotting your greenhouse gardening location is much like plotting the location of your normal garden. Make sure that there is maximum light and minimum traffic. If your greenhouse is one that will be used throughout the winter, you will want to plot your greenhouse gardening for the winter light.

2. You should make sure that you have enough room to do your greenhouse gardening. Do not fill your greenhouse to the brim with potted plants and seeds.

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Make sure that you have enough room to move around and work.

3. Greenhouse gardening is largely different from regular gardening in that you have to monitor and control the environment. To do this properly you will need to install a thermometer near the middle of your greenhouse. If temperatures get too high for your plants to be healthy you will need to ventilate the greenhouse to cool things down for your greenhouse gardening.

Maximum Yield UK | September/ October 2011

4. Greenhouse gardening requires the same soil as typical gardening. However, your plants will not need as much watering as they would outside.

This is because the greenhouse holds moisture in the air, and the soil does not dry out

as quickly. Only do your greenhouse gardening and watering when the soil is dry.

5. It is also important to sterilize your greenhouse. It is a preventive as moulds tend to develop on the greenhouse walls. It is also essential to clean the greenhouse on a regular basis because humidity and heat give impetus to the growth of moulds.

6. The water which is given to the plants should be at room temperature as your plants inside can die due to the shock of very cold water. Generally there is chlorine in tap water so you should keep the water for a day for it to disperse before watering green house plants. MY About the Author: Gary Pearson is an accomplished niche website developer and author.

Maximum Yield UK | September / October 2011

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Maximum Yield UK | September / October 2011

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Plant

Propagation Discovering Rooting Hormones

by Matt LeBannister

Understanding how rooting hormones work, what forms they come in and how to properly apply them to cuttings is essential for rooting success.

Read on to learn the benefits of liquid, gel and powder rooting hormones, including a natural weeping willow remedy.

When your plant exhibits a favourable characteristic, you want to replicate that strain’s trait in successive generations. For instance, a chilli pepper strain may be super flavourful or a tomato strain might provide a large yield. In order to ensure exact genetic copies of these super performing strains are reproduced in future plants, gardeners usually rely on cloning where cuttings are taken from a healthy mother plant.

When taking cuttings there are certain measures you can take to ensure successful rooting. Gardeners have the option of using humidity domes and root zone heating mats to speed up the rooting process of cuttings; another successful practice involves using rooting hormones. These hormones, known as auxins, are naturally available in the plant and are entirely necessary for cuttings to root successfully.

When homemade or commercial rooting hormones are applied to the site of the cutting, the auxin levels are boosted. This process leads to an improvement in the speed at which cuttings root and a general increase in the overall survival rate of the cuttings.

Rooting hormones play a crucial role in the lifecycle of every plant that has been cloned via a mother plant cutting. It is important when using any product to truly understand how it can benefit your garden.

When a cutting is taken the plant must change in order to survive. The plant must stop producing green stem cells at the source of the cut and begin producing undifferentiated cells, which will eventually turn into root cells.

Once cuttings have been placed into the growing medium their undifferentiated cells will form calluses at the source of the cut. The use of rooting hormones will quicken the development of the undifferentiated plant cells and hasten the formation of the calluses on the cuttings. This allows the root cells to appear sooner and results in healthy, vigorous root growth.

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There is some controversy as to whether it is beneficial to the cutting to be dipped in rooting hormone prior to planting. This stems from the fact that plant cuttings produce these rooting hormones, or auxins, on their own and essentially can root easily without the outside influence of commercial rooting

Cutting ready for liquid rooting hormone.

hormones.There is also a concern that adding too much rooting compound to a cutting can actually slow down the rooting process or even halt it entirely.This means that the rooting hormones need to be applied in correct doses always in regard to the specific strength and form of the hormone.

Commercial rooting hormones are available as a liquid, gel or powder. Each type has its own instructions, but there are general rules one can follow to ensure the hormone is applied correctly.

The bottom 2.5 centimetres of a cutting should be submerged in liquid rooting hormone for five to 20 seconds.

Liquid The liquid versions of rooting hormones are usually diluted in water before application. The dilution rate can vary depending on the concentration of each product, so follow the directions

Maximum Yield UK | September / October 2011

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Plant Propagation: Discovering Rooting Hormones

on the labels carefully. If the hormones get mixed too strongly in the water, then the cuttings dipped in the compound will probably have difficulty rooting. Once the rooting hormone is mixed at the correct rate, the bottom 2.5 centimetres of the cutting should be submerged for five to 20 seconds then placed directly into the growing medium. If cuttings are exposed to air too long before planting, air may be sucked into the stem, which blocks the transport of vital liquids in the plant and will kill your cuttings as a result.

versions of rooting hormones are also difficult to work with because it is very easy to over apply and stunt the root growth. The best way to ensure that the grains actually stick evenly to the cutting is to first dip the cutting 2.5 centimetres into water then into the powdered hormone. Like the previous forms of rooting hormone, it

Gel Applying the gel form of commercial rooting hormones involves no diluting of the product ahead of time, for they are ready to dip. To avoid contamination of the main supply of rooting hormone it is best to put a small amount, enough for the number of cuttings you need, in a separate container. Dip the bottom 2.5 centimetres of the cutting into the gel and make sure it covers the area evenly. The great thing about using a gel version of the rooting hormone is that once it has been applied to the cutting it seals the wound from the air. Many of the commercial gel rooting hormones—available at your local gardening shop— also contain fungicides. This will help prevent damping off fungi that will rot the stems of young cuttings and kill them in 24 hours.

A plant displaying healthy white roots, thanks to the use of a rooting hormone, is ready to be transplanted.

Powder The last type of rooting hormone is powder and it is probably the hardest to work with. This is because it can be hard to get just the right amount of the granular to stay on the end of the cutting once dipped. Powder

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Maximum Yield UK | September/ October 2011

Cuttings dipped in powdered rooting hormones should be evenly covered on the bottom 2.5 centimetres of the cutting.

is best to only put enough of any compound in a separate container. This will keep your powdered rooting hormone fresh and free of contaminants.Here is a great natural approach for those gardeners out there who prefer to do things themselves.

An easy to use, homemade rooting hormone can be derived from the weeping willow tree. The weeping willow tree contains an aspirin-like compound that when mixed with water can promote root growth 10 to 20 per cent more than just with plain water.

To make your own weeping willow water rooting hormone first collect 2.5 centimetre thick branches from a weeping willow tree. Cut up the branches into inch long pieces and soak them in water for 24 hours.

Once soaked, drain the willow water into a separate container to strain out all the chunks of weeping willow branches. The resulting brew is somewhat of a weak strength liquid rooting hormone.

The cuttings then need to be soaked in this solution for 24 hours before being planted. Cuttings need to be soaked for a long time for the weaker willow water solution to be absorbed. The benefit of using the weaker willow water solution is that there is little risk of over saturation, which ensures the cuttings root quickly and their roots grow healthy and fast.

“The weeping willow tree contains an aspirin-like compound that when mixed with water can promote root growth 10 to 20 per cent more than just with plain water.”

For cuttings to successfully root, certain expectations need to be met. Light, temperature and humidity all factor in the successful rooting of any cutting. What really allows plants to be cloned through the cutting process is rooting hormones. Natural hormones in the plant, as well as the rooting hormones that are commercially available, cause green stems cell to become undifferentiated cells. The plant then forms a callus at which time the formation of root cells begin. The commercial rooting hormone compounds simply quicken the process and give the cutting a certain edge when developing roots if properly applied.

They can give the opposite effect and hinder root growth when over applied.

Weigh the pros and cons or simply put the method to the test by growing cuttings with and without rooting hormones side-by-side and measure the results yourself. For this is truly the only way to really know whether a product works for you. MY

Maximum Yield UK | September / October 2011

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the cost of

SUNLIGHT

by Ed Harwood

Sunlight is an abundant and renewable resource, one utilized by nature, the energy industry and agriculture alike. Yet, unlike most agricultural inputs, the sun’s energy is generally left off the balance sheet, as farmers usually assume that sunlight has no monetary cost. However, contrary to popular belief, agricultural utilization of sunlight is far from free.

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We begin with an understanding of light energy. The intensity or luminance of light supplied to a plant canopy is both instantaneously and cumulatively quantified using Photosynthetic Photon Flux (PPF). The instantaneous measurement (µmoles•m2 •sec-1) plotted on a grid can be used to graph the uniformity of luminance provided to the plant canopy using a meter.Variance of intensity occurs with obstructions that create shade, distance from luminaire and with construction of bulb and reflec-

When the DLI is above the target and commensurate increases in nutrient availability are not made, the plants will suffer a number of anomalies (tip burn and bolting). The anomalies decrease yields and make plants potentially unsalable.

Exacerbating the detrimental impact of a high DLI is the considerable radiant heat generated in a greenhouse structure. The sun produces short wave radiation from wavelength 290 to 2,500 nanometers. All of this energy can be degraded to heat.

“The complexities and costs of managing the variation in natural light provides the first reason for utilizing luminaires as opposed to sunlight.“ tor in artificial lighting situations. The accumulation of PPF in 24 hours is called the Daily Light Integral (DLI).

The first cost to light utilization is managing its inconsistency. In sunlit situations DLI is impacted by the variation caused by cloud cover, diurnal and seasonal conditions. In artificial situations where variation is generally absent, it is most often calculated using the instantaneous measure multiplied by time. Work with strawberries 1 proved that the DLI is more important to plants than any peak intensity during a 24 hour period. This means we can worry less about clouds and should worry more about day length.

It is useful to compare the complexity of using sunlight to using a steady light source like artificial light. Most plant species require from nine to 20 moles per three square feet per day to grow well.

The “Monthly Light Integral” figure graphs the average monthly DLI over the year at latitude 42°. If the targeted daily integral is 17 moles per three square feet per day (red line), this target is met only for a few weeks during the year. The complexities and costs of managing the variation in natural light provides the first reason for utilizing luminaires as opposed to sunlight.

This heat makes personnel uncomfortable, some plants less productive and carbon dioxide supplementation extremely difficult or expensive when trying to use ventilation. Computerized control of motorized shading has brought high DLI under control with expense.

Insufficient DLI will alter plant growth undesirably with “reaching” (etiolation) and lack of photosynthetic capacity (often exhibited as chlorosis). During the winter months at latitude 42° the DLI is lower than the target (below the red line) without supplemental lighting. Also at this latitude low DLI months require supplemental heating in a structure not well suited to heat retention.

The second cost of sunlight is the radiant energy excess or deficiency. The traditional greenhouse using a “free” resource—the sun—is an expensive building (a special use facility with a short lifespan and high maintenance costs), and requires additional equipment (supplemental lights and shading) and energy to optimize the internal climate for yearlong use in northern latitudes. The costs come from removing or supplementing heat to keep plants and workers happy.

Some plants have a requirement for a dark period in order to thrive.

Maximum Yield UK | September / October 2011

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The cost of sunlight

Most leafy greens do not have a dark period requirement allowing 100 per cent photoperiod and consequent yield enhancement. So an opportunity lost with sunlight is gained with artificial light used 24/7 for those plants that tolerate it.

In conclusion, the management of sunlight and the associated costs of use, including structure and maintenance, temperature modifications and shading and supplementation, present the potentially more advantageous opportunity to utilize artificial light.

Of course artificial light is not perfect.

In Controlled Environment Agriculture (CEA), supplemental light (supplemental to the sun) is produced by a number of different luminaires. A luminaire is the bulb, ballast and reflector (i.e., a complete assembly providing illumination). The type of luminaire used for growing plants variably includes fluorescent, high pressure sodium (HPS)

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and metal halide (MH). The latter two luminaires are types of High Intensity Discharge (HID) lighting. Table two includes some characteristics of these luminaires.

Luminaires vary in intensity, spectrum and life affecting both the quantity and quality of the light provided. All luminaires attenuate (lose intensity) TABLE 1: Chabot, B. F., Jurik, T. W., & Chabot, J. F. (1979). over time. HID and LED Influence of Instantaneous and Integrated Light-Flux Density on luminaires do not attenuate Leaf Anatomy and Photosynthesis. Am. J. Bot. , 66:8:940-945. appreciably until very near the end of life.

The energy consumed per luminaire, percentage of total supplied energy that generally indicative of the intensity of the is the rated watts of output). The effilight, can range from less than 250 watts ciency can vary considerably with type to 1,000 watts. For HID and fluorescent and wattage as seen in the table. HIDs luminaires, the ballast consumes some of are the more typical luminaire chosen the energy supplied and other engineerfor supplemental light. Fluorescents do ing differences alter efficiency sometimes not make good choices for commercial referred to as the power factor (the facilities as they produce little light per

Maximum Yield UK | September/ October 2011

individual luminaire, when broken create a toxic spill and greatly interfere with use of sunlight.

Typical choice of luminaire is based mostly on desired light intensity (derived from the mounting distance from canopy and bulb wattage) and economics. For a greenhouse where the luminaire itself shades the plants, higher wattage is used to allow greater mounting height and lower density of luminaires. The higher wattage also obtains an improvement in individual luminaire efficiency. The voltage and phase of the electrical supply can also impact the total energy consumption Source Incandescent LED Fluorescent MH – 400 MH – 1000 HPS – 400 HPS – 1000

Total Wattage consumed (W) 40 0.025 48 425 1,060 425 1,060

vary considerably in how effectively they create this uniform surface as can be seen in figure one, which was made using two 400 watt metal halide bulbs mounted 91 centimetres above the measured surface grid of five centimetre squares. The design problem for a reflector is complex due to the need to avoid reflecting light onto the filament, to manage the varying output from the element’s glass globe and to fill the area to be illuminated evenly. When a luminaire is placed within a chamber having reflective surfaces surrounding the luminaire, these surfaces can also affect the uniformity of light. Although most reflec-

Average Life (hrs) 750 50,000 20,000 15,000 10,000 24,000 24,000

Efficiency (lumens watt-1) 12 35 66 94 118 117 132

TABLE 2: Aldrich, R.A, and J.W. Bartok Jr. 1994. Greenhouse Engineering. NRAES, Ithaca, NY. Page 99.

of a luminaire. Distance has a big impact, reducing light intensity proportional to the square of the distance.

Reflectors used in luminaires are an attempt to provide a uniform intensity over a canopy of plants. These reflectors

tors are made of shiny metal, clean white surfaces reflect light just as well with less added expense.

Given that the particular characteristics of “free” sunlight involves a range of hidden costs, which are relevant to open-air as well as greenhouse conditions, the use of artificial light has significant advantages. These include uniformity, exact intensity, consistency and precision, and, taken together, make indoor agriculture a competitive and advantageous route when compared with the caprices of nature that make farming with sunshine costly. MY Chabot, B. F., Jurik,T.W., & Chabot, J. F. (1979).

Influence of Instantaneous and Integrated Light-Flux Density on Leaf Anatomy and Photosynthesis. Am. J. Bot. , 66:8:940-945.

Aldrich, R.A, and J.W. Bartok Jr. 1994. Greenhouse Engineering. NRAES, Ithaca, NY. Page 99.

Maximum Yield UK | September / October 2011

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Chelated

Micronutrients

by Donald Lester

Agricultural scientist Donald Lester details the benefits of highly efficient chelated micronutrients—that aid in enhanced plant growth and greater yields—and defines the various types to help you choose the very best option for your indoor garden.

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Maximum Yield UK | September/ October 2011

Photo by Dennis Tasa

Plants need the essential nutrients nitrogen, phosphorus and potassium—the N-P-K on fertilizer labels—in large amounts, so these are referred to as macronutrients. Plants also need essential micronutrients (also known as trace minerals) such as calcium, zinc, magnesium, iron and manganese. Micronutrients come in many different forms that affect their solubility (i.e., dissolvability) in water and their uptake and usage by plants.

Micronutrients commonly react with other chemicals and get “tied up” or precipitate in the soil. Once this happens the micronutrients are insoluble in water and will not be absorbed or used by the plant, at least not until microorganisms or weather breaks them down into a usable form. So, you could literally add a lot of one micronutrient to the soil but the plant will use only a small amount. A good example of this phenomenon can be seen with the soft mineral gypsum. Every year growers apply gypsum to their fields by the ton, but since it is not very soluble in water only a very small amount of calcium is available to the plant. It takes a long time for soil microbes and weather to break down these compounds so that plants can use them. Foliar applications do not suffer from this phenomenon (table one).

Gypsum, a soft mineral composed of calcium sulfate dihydrate, is only mildly water soluble, so only small amount of calcium becomes available to plants.

Maximum Yield UK | September / October 2011

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Chelated Micronutrients

Nutrient

Crop

Foliar

Soil

Citation

Zinc (ZnSO4)

annual crops

1

12

Lingle & Holmberg (1956)

Phosphorus (H3PO4)

beans, tomatoes

1

20

Wittwer, et al. (1957)

Iron (FeSO4)

grain sorghum

1

25

Withee & Carlson (1959)

Magnesium (MgSO4)

grain sorghum

1

100

Krantz (1962)

Magnesium (MgSO4)

celery

1

50 to 100

Johnson, et al.(1957, 1961)

Table 1. Relative amounts of nutrient needed for comparable effect in the plant, by method of application.

Fertilizer manufacturers produce several different forms of micronutrients such as salts, oxides and chelates. The chelated micronutrients are becoming popular because of their high efficiency.

Knowing a bit about the various types of chelated micronutrients can help you choose the one that is right for you.

What is a chelate?

Chelation is a term that describes an encapsulation process. A mineral, like calcium for example, reacts with another material to form a protective shell around the desired mineral or metal (in this case calcium). The word chelate derives from the Greek word “chel”, meaning a crab’s claw, and refers to the pincer-like manner in which the mineral is bound. Some chelating chemicals are shaped like a letter ‘C’ and surround the mineral with just one

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molecule. This type of binding is called a “complex”. When two molecules of the same material surround a mineral it is known as a chelate. It is important to note that some minerals, like boron or molybdenum, have only one chemical bond and are thus limited to forming only a complex.

Strictly speaking, boron and molybdenum cannot be chelated minerals but they are often presented and sold in the market as chelated minerals.

Chelates need a “glue” to hold the protective shell in place. Some chelates

use sodium for this purpose, but adding sodium can be detrimental to plants. In general the amino acid chelates use organic acids like citric acid. There is an important distinction to be made here about the use of the word organic. In chemistry the term organic means the material contains carbon. In the organic foods world the term organic refers to foods produced without pesticides, synthetic substances, sewage products and other restrictions.

Chelates are molecules with a neutral charge, which is very important. Micronutrients normally have an electrical charge on

“Some materials applied to leaves do not enter the tissues but instead remain stuck to the leaf surface like house paint.” them. For example, calcium and magnesium are both +2 charge.

Soil is generally negative in charge, especially clay soils. This means that calcium and magnesium will likely react with the soil and be insoluble and not available for plants to use. Moreover, since they are the same charge, calcium and magnesium compete with each other for entry into the plant. Pores on the leaves of plants (also known as stomates) are negatively charged, so positively

charged molecules trying to penetrate the plant get tied up at the stomate entrance thus slowing absorption. But the interaction with chelates is very different. The neutral charge of chelated minerals allows them to enter the stomates unimpeded. Research into nutrient uptake has shown that some materials applied to leaves do not enter the tissues but instead remain stuck to the leaf surface like house paint. Subsequent chemical analysis of these tissues would show similar nutrient levels as those tissues that had nutrient penetration. In light of this oversight researchers now apply nutrients to the leaves and then analyze the fruits to measure the amount of nutrient movement inside the plant.

There are several types of chelates. One of the most common forms is Ethylene Diamine Tetraacetic Acid (EDTA), which has been on the market for years. EDTA is a large synthetic molecule that binds very tightly to miner-

Maximum Yield UK | September / October 2011

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Chelated Micronutrients

als and resists chemical interactions—desirable characteristics for chelates used in the soil. But this strong bonding characteristic can be a negative attribute once EDTA is in the plant. EDTA binds tightly. In fact, when people have heavy metal poi-

“Amino acid chelates are especially suitable for greenhouse and hydroponics systems because they are usually certified organic, readily available for uptake by plants by both roots and foliage...” soning EDTA is injected into their bloodstream to chelate the metals and filter them out. Obviously patients do not want EDTA releasing heavy metals back into their body prematurely. In addition, EDTA can solve one plant nutrient deficiency and at the same time cause another. EDTA has something of a separation anxiety; it must always hold on to something. For example, iron EDTA will cure iron deficiency in plants, but in order for the EDTA to re-

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lease the iron it must hold onto something else. Often EDTA will take up manganese in order to release the iron, thus causing a manganese deficiency. Furthermore, EDTA is known to take calcium from cell walls in both plants and people. For this reason people put on EDTA are often instructed to take calcium supplements as well.

Plants losing calcium in this manner (primarily from their cell walls) visually manifest the loss as wilting.

Another category of chelate is the amino acid chelates. There are 20 amino acids. Amino acids are the building blocks of protein. Amino acids are moderately strong chelating agents. Once inside the

plant the mineral is released and the leftover amino acids that formed the protective shell are used by the plant as a source of water soluble nitrogen. After all, amino acids are building blocks in cell machinery.

Everything is used, nothing is lost. Conversely, EDTA is a synthetic molecule, and plants do not naturally use EDTA. It’s sort of like trans fat; the human body doesn’t know what to do with it. Amino acid chelates are generally systemic in the plant meaning they move and travel to where they are needed.

They can do this because amino acids are recognized by the plant as building blocks and are used in nearly every tissue in the plant. Amino acid chelates are available as liquids or powders and generally available for use in organic food production.

Glycine chelates (also known as glycinates) are a subset of amino acid chelates. Glycine is the smallest amino acid and it is often used as a chelating agent. Since glycine is small it makes a small final product that passes through leaf pores (stomates) more easily than other larger molecules, thus enhancing plant uptake. And don’t forget, glycine chelates have glycine, which is an amino acid. When the glycine is separated from the mineral in the plant, the plant uses the glycine. Glycine chelates are sometimes used in wine production because they supply not only the desired nutrients, but the glycine also supplies Yeast Available Nitrogen (YAN). This means that the yeast can break down the glycine and use the nitrogen in the formation of its cell walls.

Because chelates enter the plant easily they are extremely useful for quickly correcting nutrient deficiencies. As a rule chelates are very safe for the plant. The amino acid chelates (glycine chelates included) require large amounts of product to be applied in order to be toxic to plants. But care must be taken to avoid phytotoxicity or burning of plant tissues with EDTA.

Shopping for chelated micronutrients Desirable Characteristics

Undesirable Characteristics

Formulation is safe for plants

Formulation is prone to burning

Does not promote other deficiencies

Needs ion replacement to release micronutrient

Readily available to the plant

Slow uptake

No sodium

Contains sodium

Organic certification

Not organically certified

Using amino acid chelated micronutrients Amino acid chelates are especially suitable for greenhouse and hydroponics systems because they are usually certified organic, readily available for uptake by plants by both roots and foliage and generally are not phytotoxic. For example, in aquaponic systems where fish are integrated into the hydroponics system it is important that nothing synthetic enter the tissues or meat of the fish. Therefore, the use of organic materials is an obvious choice, and the amino acid chelates can be applied directly to the foliage or to the nutrient solution for immediate correction of nutrient deficiencies.

When shopping for chelated minerals look for the characteristics listed. MY

Maximum Yield UK | September / October 2011

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you tell us Robbie den Hartog, owner/director of Metrop, talks to Maximum Yield about foliar fertilization, degradability and solubility, and Hydroponics for Africa.

Fertilizer is the strongest P/K booster on the market.

Also standard in all our fertilizers are high amounts of micro elements that work like stimulators. What others put in 10 or more bottles we put in only three bottles.

Metrop fertilizers can be used on all mediums. We don’t have a fertilizer for every different medium or system; we just have one line. With our products you get more and pay less. After all, who wants to buy expensive water.

MY: What makes for a well-balanced fertilizer?

Robbie: The right ingredients and the right mixing processes.

Chris Fischer, sales (centre) and James Debs, Metrop USA (right) with a Swiss client (left) at the San Francisco Indoor Garden Expo.

Maximum Yield (MY): How do your fertilizers produce maximum yields and a quality product? What ingredients make these results possible?

Robbie den Hartog: The ingredients are a secret. Our fertilizers look like thick yogourt and are highly concentrated with maximum dilution rates of 100 millilitres per 100 litres of water. In addition, all our products contain a standard wetting agent so they can be used as a foliar fertilizer.

The big differences between the NPK elements in our products result in bigger, fatter growth. For example, our MR2 Flower Fertilizer contains 40 per cent potassium, and we all know that potassium creates fat flowers and fruit, especially when the potassium is mixed 2/1 with phosphorus. Our basic MR2 Flower

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MY: What does it mean to say that a fertilizer is degradable and soluble?

Robbie: Our fertilizers are highly concentrated liquids and soluble.

When mixed in water they dissolve quickly.

Our fertilizers are biologically degradable meaning each element in each product can be used as food for the plant. No elements are unused in the soil and no excessive elements remain that could harm the environment.

MY: Where can end-consumers purchase Metrop fertilizers?

Robbie: Metrop fertilizers can only be purchased from our premium dealers that we carefully and personally hand-select.

you see the results, you will believe it.Through September and October we are giving away starter sets to anyone who wants to test our products before committing to purchasing. All you have to do is e-mail info@metrop.nl with your name and the address of your favourite hydroponic shop, and we will set you up.

MY: What is Hydroponics for Africa and how is Metrop involved in supporting this organization?

Robbie: Hydroponics for Africa is an organization that sets up small hydroponic farms in Africa where they have to pump up the water from deep out of the ground. We provide them with fertilizers at cost price and give them hydroponic and plant advice so they learn to grow different kind of crops.

MY: What products in the Metrop line are you most excited about right now?

Robbie: All our products are high quality, but number one in hydroponics and the professional horticulture market is the Calgreen. Calgreen adds weight in the plant and protection against pests and disease. Calgreen makes all the cell walls thicker, hardier and heavier. That is why we call Calgreen cement for the cells.

MY: What other products do you offer to hobby growers in the UK? Robbie: In addition to Calgreen we offer the concentrated fertilizers MR1 Grow, MR2 Flower, MAM motherplant fertilizer, and AminoRoot and AminoBloom hormone stimulators.We also produce fertilizers for some other brands, all designed to produce the highest yields.When you use it, you will see the results.When

MY: What strategies has Metrop implemented to lessen their environmental impact on our planet?

Robbie: We recommend professional and hobby growers to apply our products as a foliar spray. A foliar application is much more effective than root applications as there is no waste. All of our products are biologically degradable because we want harvests to be good this season, and we want our children to be able to grow in the same soil for years to come.

Our products are extremely concentrated, so instead of buying big cans of fertilizers you only need to buy a few litre bottles of Metrop. The environmental savings extend to transportation. One pallet of Metrop fertilizers compares with 10 pallets of another brand. Less transport, less storage and less waste equals a lower environmental impact. MY MY: How/where can Briton readers of Maximum Yield find out more about your company and products?

Robbie: Visit www.metrop.net or one of our premium dealers. For premium dealers contact our UK distributer Easy Grow Grimsby at +44 (0) 1472 346900.

Maximum Yield UK | September / October 2011

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TALKING SHOP

the

greenhouse effect AT A GLANCE Store Name: The Greenhouse Effect Hydroponics Ltd. Owners: Adam and Katharine Clarke Location: Unit 2 Eagle Farm, Cranfield Road Wavendon, Milton Keynes, Buckinghamshire MK17 8AU Phone: +44 (0) 1908 585283 Web: www.thegreenhouseffect.co.uk E-mail: info@thegreenhouseffect.co.uk Motto: “Stock quality products, offer quality advice.”

The Greenhouse Effect team from left: Adam, Kath, Richard and James

People come to the retail hydroponics business from a lot of different directions. Adam Clarke was a carpenter who spent 10 years building grow rooms and hydroponic set-ups for his clients and saw a great opportunity.

Adam and his wife Kath opened The Greenhouse Effect in May 2001, converting an old farm unit into retail premises. Eagle Farm is the perfect space, located within five minutes of both junctions 13 and 14 of the M1 and offering easy access for local customers from both Milton Keynes and Bedford. It was also easily accessible for

Setting up a commercial-sized project.

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Maximum Yield UK | September/ October 2011

Impres

sive ro

ots in g

row roo

m.

customers from both the north and south of England.

“Alongside the success of the shop, Staffing was their initial challenge and for the first couple of years we are very proud that our expertise in the couple pretty much ran the whole show on their own.

“Adam ran the shop on his own six days a week all year round,” hydroponics has led us to work closely Kath explains,“with me providing the administration support. Even with Trees4Good.” when his first son was born he waited until the last minute to shut the shop and whisk me to hospital!”

Inventory was the next hurdle.“Adam has become an expert in The personal touch this family approach provides is just what the stock rotation,” Kath tells us.The business has grown organically, customers are looking for, according to Adam, and it’s how they plan to with all revenue being reinvested into the business for the first five go on. years, and as the business has grown so have the number of product “Our main strength is our ability to work together—everyone is ranges that we carry.The main thing Adam has learned is to know aware of all the customers’ needs, to ensure consistency of service and his customers—their grow schedules, systems, food, the ability to advice.We are often praised for being able to sort out problems cusanticipate what they will need tomers come to us with and by asking the and when, and ensuring that we right questions and listening to the answers always have in stock what our we are able to offer honest and quality advice customers request.” and ensure we get to the root of the prob“We are also in the unique posilem,” he explains.

Adam and Kath are proud of the great tion of being the sole distributor strides they’ve been able to make since their of the O2XS dissolved oxygen first small retail opening in 2001, and they system,” he tells us.“The O2XS deep-water culture system takes don’t plan to slow down any time soon. hydroponics to a new level, al“In terms of revenue and turnover we are lowing consistently higher levels now in the top 10 of hydroponic retail shops of dissolved oxygen than any in the UK—which is no mean feat when other hydroponic system on the you consider there are now over 400 shops market today in the world.These in the country,” Kath says. systems are manufactured by our And their expertise has not gone unnosister company—Growing Made ticed in the larger circles of the industry, Easy Ltd—on the same premises either. “Alongside the success of the shop, as the shop.” we are very proud that our expertise in They’ve got plans for more exhydroponics has led us to work closely pansion.“As we continue to grow with Trees4Good, Green Energy Plantawe are already in negotiations for tions and R&R Biotek, in both the UK a 10,000 square foot flagship shop and Borneo. Having designed and built on the farm,” Kath tells us. large hydroponic nurseries in Borneo to Predictably, their inventory has propagate and nurture trees for planting A working grow room thrives in the middle of the shop. grown along with their retail in logged areas, Adam has also provided space and The Greenhouse Effect is now one of the best-stocked consultancy services for both the Sabah Forestry Research Centre hydroponics shops in the country. and the Tenom Agricultural Park, working alongside respected Kath and Adam have found some solutions to their early staffing horticulturalists including Anthony Lamb,” Kath says. issues now too, turning to family and close friends to provide the So what does the hydro business look like to Adam and Kath committed service their loyal customers expect. now that they are industry veterans with a successful company to “There are now four members of staff, a real family business,” their credit? says Kath, “Adam’s brother James was recruited from Canada “Our company philosophy has never changed—stock quality where he had extensive experience in both indoor and outdoor products, offer quality advice. It’s why our customers come back growing; a close family friend, Richard, had also been involved to us again and again. It’s not for the cheapest price, but because in the industry for a number of years before joining our business. they know the products are good, they know they will only be The fact it is a family business we believe enhances our relationsold what they need when they need it, and because they know ship with our customers—it’s our baby and we want it to succeed they will always get great advice.Valued products have value— for many years to come, so it is in all our interests to provide the don’t always go for the cheapest product or quote; it’s what you best advice and service.” get with it that is invaluable!” MY Maximum Yield UK | September / October 2011

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Maximum Yield UK | September/ October 2011

DO YOU

know?

1

The soft mineral gypsum is not very soluble in water so when it is applied, only a small amount of calcium is available to the plant.

2

In chemistry the term organic means the material contains carbon. In the organic foods world the term organic refers to foods produced without pesticides, synthetic substances, sewage products and other restrictions.

3

Adding too much rooting compound to a cutting may slow down the rooting process.

4

Most leafy greens do not have a dark period requirement.

COMING UP IN November - December 2011 Hydroponic H2O: Water Quality and Treatment

Just because the water coming out of your tap is clear and healthy for you, doesn’t mean your plants will feel the same way. Dr. Lynette Morgan describes what problem water looks like and solutions to them.

Climate Controllers: Calibration for Indoor Gardening Success Isabelle Lemay and Mélissa Léveillé help you achieve that perfect recipe for big yields by using precise calibration instruments.

Beneficial Soil Microbes Discover what a handful of competitively-experienced growers already have from experimenting with a promising soil microbe; it is many times smaller than even the microscopic fungi mycorrhizae, and it’s called Azospirillum.

+

Innovative instrumentation, ballasts and blazers, cloners, trimmers, grow tents and more!

www.maximumyield.com Maximum Yield UK | September / October 2011

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MAX-MART

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Maximum Yield UK | September/ October 2011