Garden Culture Magazine: UK 11

IN THIS ISSUE OF GARDEN CULTURE: 9 Foreword

46 Selecting a Greenhouse Manufacturer

11 Product Spotlight

50 Who’s Growing What Where

16 The Hydroponic Stigma

52 Anecdotal Evidence

19 Food Act

54 History of Hydroponics

20 Water – much more than Wet

62 Powder to the People

28 The Problem with Iron

64 What are Phosphorus... Potassium

32 U.K. Food Policy

68 It Starts with a Seed

37 Five Cool Finds

72 Or… a Clone

38 Bananas: Abusive Fruits

76 Light Matters – part 1

44 Clover

Garden Culture™ is a publication of 325 Media Inc.

Sometimes we have to look back to see what is in front of us. We all make mistakes, and hopefully, learn from them.

When we are children we learn from our parents, peers and teachers - we must in order to survive. “Don’t touch the fire.

Stay away from traffic. Don’t talk to strangers”... and so on. As we grow up, we have to make decisions for ourselves. “Who should I vote for? Is this job right for me? Should I fear (or hate) someone, because they are different than me?” Or simple choices like, “Should I eat processed foods, or grow a garden?”

All these decisions are based on our belief systems, and the fundamentals of who we are.

When I was a boy the apples I ate were sprayed with DDT (colorless, odorless water-insoluble insecticide, C14H9Cl5). We were told it was safe, but of course, it turned out to be poison.

The issues today are no different than they were 40 years ago.

Mega corporations tell us their chemicals are safe, that our food is safe - to enjoy another Coke, and shut up. Well, they are wrong.

The chemical-laden genetically modified food is not safe, and the plethora of health issues that simply did not exist 100 years ago proves it!

We need to wake up, and stop trusting mega corporations and our governments with our health. There are many things we can’t change, or have very little influence over, like war and global politics. But food is not one of them. Granted, not everyone can afford to eat only organic food, and in some cases it is not even available, but we can start by changing our purchasing habits, to not buy ultra-processed foods, sugary sodas, and so on.

Ignorance and apathy are our enemies. It’s time to start giving a shit about what is happening to our society, and start making our world a better place for future generations.

In 100 years, I hope that our generation will be known as one that changed things for the better - because if we don’t, Monsanto may be writing the history books. 3 Eric

ED I TO RS Executive Editor: Eric Coulombe Email: eric@gardenculturemagazine.com Senior Editor: Tammy Clayton Email - tammy@gardenculturemagazine.com V P O PER AT I O NS: Celia Sayers Email: celia@gardenculturemagazine.com t. 1-514-754-1539 DESIGN Job Hugenholtz Email - job@gardenculturemagazine.com Special thanks to: Our writers Judd Stone, Amber Fields, Evan Folds, Everest Fernandez, Stephen Brookes, Tammy Clayton, Grubbycup, Shane Hutto, Theo Tekstra, Jeff Edwards, and Helene Isbell.

PUBLISHER 325 Media 44 Hyde Rd., Milles Isles Québec, Canada t. +1 (844) GC GROWS w. www.gardenculturemagazine.com Email - info@gardenculturemagazine.com ADVERTISING Eric Coulombe Email - eric@gardenculturemagazine.com t. 1-514-233-1539 D I ST R I B U T I O N PA R T N ER S • Down to Earth Kent • Maxigrow • Nutriculture DGS • HydroGarden • Highlight Horticulture Website: www.GardenCultureMagazine.com

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The Autopot Watering Syste m is an ingenious set up for growing plants, and one tha recommend to anyone. Fro t I can personally m acres of commercial gre en ho us es, to the little indoor garden in basement or attic;Autopo your t’s simplicity and the result s will impress even the mo st seasoned grower.

I have been growing in Autopots for the past year, and have been seriously impressed. Everything I have tried has turned out amazing. Tomatoes, cucumbers, thyme, kale, and lettuce all did so well, I decided to test out some new plants. I cut up a piece of organic ginger, and buried them 2” deep. And 5 months later... I harvested over 3 pounds of the best ginger I have ever seen. I now also have turmeric and a grape vine, which are both growing quite vigorously.

There are several things that differentiate this system from other growing methods.

1. AutoPot Watering Systems keep plants watered using gravity pressure alone; no need for electricity, timers, or pumps.

2. They are environmentally friendly, very little water is ever lost. Some commercial growers have recorded savings of up to 50% in their water and nutrient consumption.

3. AutoPot uses patented AQUAvalve technology; the only watering system in the world where each individual plant controls their own irrigation, and receives fresh nutrient-enriched water exactly when they need it.

How It Works…

Once connected to a reservoir the AQUAvalve will open, and allow water to fill the tray to a pre-set level of 20mm.

The AQUAvalve will not refill the tray until all the water has been used. Simple!

Watch the video: www.bit.ly/AP-valve By consistently meeting their plants’ requirements, growers using AutoPot achieve impressive yields, with less time and maintenance, whilst reducing their water and nutrient consumption. I honestly cannot say enough about this system. It really was love at first grow.

The all new Hyper Climate Control is designed to thermostatically adjust airflow (via variable fan speed) into your grow space on both warm days and cold nights. As cold air can be detrimental to plant health during night cycles, the Hyper Climate Control drops fan RPM’s down to a minimum to keep the plants warmer, and maintain just enough airflow for effective carbon filter operation.

During warmer daytime temperatures the Hyper Climate Control will lift and regulate fan RPM’s to maintain your digitally selected maximum ambient temperature. Set two dials only once at the beginning of each cycle, and forget it! · Extremely easy to use - Set and forget! · Lowest energy use of any fan/filter/controller. · Thermostatically changes fan speed/RPM’s. · Constantly maintains optimal daytime temp. · Slows fan speed to low RPM’s on cold nights. · For use on digital EC HyperFans only.

Maxibright NOW sells Sunmaster Co mpacts in 250W, 400W and 600W versions, pr oviding even more choice for grow ers.

Find your local retai ler: maxibright.com /where-to-buy/

biostimulant that is designed Moonshine is a brewed plant growth, health and terpene to promote impressive plant production.

Big Benefits: t size • Over double previous roo esis nth • Increased photosy ed yields • Faster maturity and increas • Increased insect resistance t growth • Contains NO synthetic plan regulators • Contains NO silicone o, type into To view the Moonshine vide your browser: SVID http://tinyurl.com/MOON

TLEDs from Secret Jardin offer an affordable, efficient, and versatile way of lighting your grow room. The 26W TLEDs are available in (Blue) Growing 6500°K, or (Red) Blooming (Red mix - including infra-red, 2100°K, and 3000°K LEDs) options. The TLED is 93% more efficient than CFL lighting in terms of PAR per watt. Flexible TLEDs can be hung vertically or horizontally from grow tent poles

The Monkey Fan from Secret Jard in has two speed settings, is height adju stable, and easy to install. · 13Watts – 2200 RPM · Stays in position · Compatible with grow tent pole s 16 - 19mm To view the Monkey fan installat ion video, type into your browser: http://tinyurl.co m/MONKEYFAN

16-19mm using the hooks and clips provided, or suspend your TLEDs from the grow tent using traditional methods, like Maxibright Easy Hangers.

To view the easy installation of the TLED, type into your browser: http://tinyurl.com/SJTLED

You can now use the DAYLIGHT 315 digital power pack with any reflector that has an E40 lamp holder, by using the E40 to PHILIPS 315W lamp holder adapter. The E40 adapter is quick and easy to use. Simply screw the E40 adapter into the E40 lamp holder on your reflector, then install the PHILIPS 315W CMH/CDM lamp as normal... and you are ready to go!

Find your local retailer: maxibright.com/where-to-buy/

The Daylight 315 ballast system uses an advanced electronic ballast to power the Philips Elite Daylight 315W CMH/CDM (Growing) and Philips Elite Agro 315W CMH/CDM (Flowering) lamps for excellent

The Xpert 600W – is a low cost, vented, powder-coated metal enclosure ballast with 600W of Genuine Power. The Xpert power pack has a precision-wound ballast, a matched digital SmartTM igniter, and is manufactured using quality components from Venture Lighting. The compact size of the Xpert (L: 245mm x H: 110mm x W: 120mm) makes it ideal for wall mounting and grow room use.

PAR per watt output.

Plants that grow under a full spectrum throughout their growth cycle benefit from a more natural quality of light proven to prevent stretching, and encourage higher quality growth. Culminating in strong, healthy growth, and high quality yields.

Find your local supplier: maxigrow.com/where-to-buy/

Find your local retailer: maxibright .com/ where-to-buy/

• •

The Maxibright DUO uses Filp/Flop technology to alternately illuminate two separate grow rooms automatically when set to the 12 Hour Flip/Flop setting.

Or use the DUO 1 Hour Flip/Flop setting with two lamps in one grow room to half the lamp heat, and significantly reduce the grow room temperature.

Maxibright DUO one of the most versatile ballasts ever!

• • • • • • • • • •

F lip/Flop Technology Six Power Settings: 25W, 275W,

400W, 440W, 600W & 660W Surge ControlTM Soft Start Technology Fast Lamp Re-strike Dynamic Frequency Control End of Lamp Life Detection Short Circuit Protection Thermal Protection, Auto Reset LED Status with Diagnostic Feature Silent, Lightweight & Wall Mountable Runs HPS & MH Lamps

As most of you know, hydroponics is an extremely productive and efficient gardening method to grow almost every kind of plant imaginable. Yet, hydroponics seems to be, at least socially, directly associated with the growth of plants that are illicit.

.kojisproduce.com/ credit: http://www

Why is this? After all, hydroponics, from a scientific standpoint, is the best way to grow anything for large yields, and overall plant health and vigor. Hydroponics also offers the most efficient way to farm while conserving water resources, as most systems lose very little to evaporation and mostly to plant uptake, while the rest is recycled back into the aquifer. Statistics from the now defunct Progressive Gardening Trade Association showed that customers of most indoor gardening centers were actually media gardeners, and few employed water culture methods.

Some years ago, I managed an indoor gardening center that had to tailor its very conduct around the stigma that leaned against its very credibility. There was a company policy in place that if anyone so much as muttered anything about any sort of illicit plant, they had to be shown the door.

It was a don’t ask, don’t tell policy that left me giving advice on how to grow food to a customer base that in my mind was at least a large percentage questionable. Even though confident many customers were in fact growing veggies, as they would share them, I had bought into the stigma.

One day a nurse and her patient come to visit the store. The patient is paraplegic, and his nurse is pushing him in. I’m almost certain, stuck in my tunnel vision, that he is here to learn how to grow something that may help alleviate some of his discomfort. Although, I would like to help this man, I also need to follow the law, and I’m immediately hoping he doesn’t say something that causes me to have to ask him to leave.

He rolls up to the counter, and has trouble speaking clearly, so we communicate through his nurse. His name is Tom Kojis.

He has Cerebral Palsy. He’s the son of a farmer with stubs for hands. He planted his first batch of corn in 1972. He was the editor of his local newspaper for many years. He operates a CSA called Koji’s Produce. He’s got a lot to teach, but he’s here wanting to learn how to expand his urban farming into his basement with hydroponics.

Urban farming? Yes, his father who still owns the farm, sublets enough space to Tom to grow corn, but the rest of the operation happens in his modest fenced city lot - on a litany of custom made benches, and in 4 greenhouses he has in the back yard. An elevator will lead you into his basement where Tom uses a General Hydroponics’ Aeroflo to produce romaine lettuce in the winter time, along with a Volkswheel.

Although he’s been at it since the 70’s, Tom is always looking to improve his gardening prowess, and since we met, has designed and built many different hydroponic systems with varying results. He operates 2 produce stands, and offers service to his community in Waterford, Wisconsin - right from his front porch, named Kojis Produce in 2005.

Tom is such a successful urban gardener that he has been able to donate over 10,000 pounds of fresh produce to local food banks, multiple years in a row. Tom’s ideas for the future include expanding his reach into local restaurants that are demanding better quality, pesticide-free produce to include in their dishes.

Tom has had to train all sorts of people just to lend him a hand on the farm over the years, and this spawned the idea of someday creating an urban farm/classroom environment on the site to teach physically disadvantaged children and teens about urban farming practices, and about Tom’s being able to overcome similar hurdles to become the successful urban farmer he is today.

I judged Tom the day he came into the store, and unrightfully so.

Urban farming and hydroponic culture are the future of farming period. Its methodology is going to be a contributing component of food security in the not so distant future. I couldn’t be more overjoyed and thankful to have met Tom Kojis, and to have helped him work through the innovation he represents today.

This is an awareness article, and an open apology letter.

Don’t ever judge a book, a customer, or a store by its cover. 3

At the end of September 2015, California Governor Jerry Brown signed AB 2561 into a state civil code law. Naturally, a host of blog posts, forum discussions, tweets, and hashtags erupted as word spread across the internet. It is about time that government did something that makes it not illegal to grow fresh food at home. And The Neighbourhood Food Act voids language in leases and homeowner association bylaws to make this happen.

BUT...

Few involved in the chatter took time to read past the headlines. Many assume this means that Californians can suddenly tear out all the landscaping, and turn the entire property into a vegetable garden. The law stops landlords and HOAs from levying fines on residents for growing fruits and vegetables, and otherwise punishing them for doing so. But it isn’t license to grow your own just anywhere. It sets specific limitations to protect residential property values, and maintain attractive neighbourhoods.

First, it defines what types of housing it applies to for renters and HOA members. The right to grow food despite lease stipulations only applies to one and twounit buildings. Landlords cannot prohibit renters of single family homes or duplexes from having a vegetable garden.

HOA developments have bylaws that govern common neighbourhood interests, and AB 2561 removes barriers to gardening for both renters and owners in appartment complexes, planned housing developments, and community apartments.

Secondly, this is not about urban farming. It’s a personal agriculture provision. The produce grown under this law can only be for personal consumption, though the Sustainable Economies Law Center advises to check local planning and environmental health agencies regarding selling the harvest.

The language states that the law only removes restrictions on private areas, and that such gardens must be in the backyard. In appartments, food growing is confined to containers in their personal space. A landlord can also allow container gardens only to protect the state of the property.

But the front yard turned veggie patch is not allowed. HOAs can still levy fines for dead plants left standing, weeds, and poorly maintained or unsightly backyard gardens.

This is a step in a very positive direction for many Californians, but particularly for those living in food deserts and urban environments. SELC sees this as legislation that will evolve.

Other states, and even other countries, should take note, because food deserts are a huge problem across the US, and the poor lacking access to good food is a global issue.

More Details: www bit.ly/food-act-faq 3

Let’s put it this way, water is much more than just wet. In fact, with water, the further we look, the less we know. As D.H. Lawrence said in his book The Third Thing, “Water is H2O, hydrogen two parts, oxygen one, but there is also a third thing that makes it water. And nobody knows what that it is.”

20

Water may be the most obvious substance in our daily lives and, at the same time, one of the greatest mysteries on the face of the Earth. Water is everywhere and nowhere all at once, showing up in the dew of the morning, and reappearing as a fog rolling through the hills at dusk.

The character of water is one of grace under pressure, constantly seeking its own level without prejudice. We should be more like water according to Bruce Lee, “Empty your mind, be formless, be shapeless… like water. Water can flow, or it can crash. Be water my friend.”

modern popular science with all of its authority, expertise, and experience has never actually seen a water molecule.

Major religions describe water as a seminal substance, and at the same time destroying the Earth in great floods. Water floated the Titanic, and sunk her at the same time. In more ways than one, water is a vital conundrum in regards to humanity and modern popular science.

What is water, anyway?

Water can be structured and energized, and has a capacity to listen and remember.

Water has personality and is happier, more productive, and capable of supporting life when we provide the forms, conditions, and vibrations that it likes. Water is the most sensitive substance on Earth, and it has incredible capabilities when respected and treated appropriately.

It may seem strange to give water sentient characteristics, but it is so pervasive, fundamental, and important that there is a limitation of language when it comes to its descriptions.

Besides, rarely, if ever, do we stop and consider what water wants. It is collectively a passive substance in our lives.

Water expresses elegance in the grace of a babbling brook, and power in the force of a whirlpool, or an epic surfing wave at Jaws or Pipeline. For such a common substance, it turns out we retain a surprisingly limited understanding of its origins, abilities, and secrets.

Where does water come from? How many different kinds of water are there? What is water, anyway?

The truth, on all accounts, is that collectively we don’t really know water for what it is, or where it comes from. We experience water more than we understand it.

Everyone knows the H2O chemical structure of water from chemistry class, but you may be surprised to discover that

Water has an unusually high melting and boiling point. In some cases, hot water may freeze faster than cold water. It’s called the Mpemba effect.

Did you know there are at least nine different kinds of ice, and over 80 different properties that are measurable and able to be manipulated in water?

Water has a high viscosity, or resistance, relative to other liquids. This also allows it to retain heat to help regulate our weather, and be a great facilitator of sound waves.

Almost nothing behaves the way expected when it comes to water, pressure actually reduces ice’s melting point and thermal conductivity, and actually causes water molecules to move further away from each other. Makes no “scientific” sense - but so it is with water.

The strangeness of water is a result of its polarity, or the expression of both a positively (+) and negatively (-) charged side to its molecule, represented by the V shape chemical structure seen in textbooks. The polarity of water makes it capable of combining with and dissolving anything, giving it the moniker the “universal solvent”.

One of water’s many roles is to pick stuff up and carry it around. This includes delivering oxygen and nutrition inside living cells, and carrying away the toxins, and also in creating macro structures like stalagmites, or the Grand Canyon.

But it doesn’t always work in our favor. Water holds things in a way to make them imperceptible, like an

invisibility cloak that prevents us from seeing the substances held within. We are mesmerized by its uniformity, and at the same time unaware of its potential for toxicity. Herein is the threat of runoff from conventional agriculture and lawn care, and public policies - like water fluoridation, and chlorination.

One of water’s many roles is to pick stuff up and carry

Only about 0.036% percent of the planet’s total water supply is found in lakes and rivers, which is still thousands of trillions of liters.

Relative to the mass of our planet, water is the equivalent of the skin on an apple.

Water is life, but it also allows us to engage life. To create 1 ton of steel it takes 272 tonnes it around of water. It takes an average of 1741 liters of Because water is a polar molecule and water to make a 110 grams of hamburger. A opposite charges attract, water hugs itself nuclear power plant requires 113 million liters through a process called hydrogen bonding. We see the of water to cool its reactors… every hour. influence of hydrogen bonding in clouds, the meniscus in a glass of water, or the ability of water striders to walk on In fact, one of the most important parts of food is water. Not water, creating an entire ecosystem called a neuston. only is it required for plants to grow, but upwards of 95% of plants and 75% of the human body are comprised of water.

We owe our very existence to these anomalies of water.

Without water, we die. It is possible to survive for weeks, Due to its distinctive molecular structure water exhibits even months, without food; but without water - we can last its greatest density and carrying capacity at 4°C with the only days. density actually decreasing below this temperature. This is why ice floats on liquid water, which is relatively unique in Water is abundant, yet scarce. Almost half the world doesn’t Nature, and quite significant. Imagine if water froze from have access to clean water, or has to walk to get it. Most the bottom up, would life have survived ice ages on the people in the world rely on an average of 5 liters of water a bottom of solid lakes? day. In the United States, on average, we use that much water every time we flush the toilet.

There’s something like 1,260,000,000,000,000,000,000 liters (1.26 sextillion liters) of water found on planet The modern world is only just beginning to feel the economic Earth. About 70% of the planet is covered in ocean, and societal pressures of peak water, and water security. and almost 98% of the water on the planet is in the Business moguls are buying up aquifers and water rights. oceans. About 2% of Earth’s water is fresh, but 1.6% of Cities are privatizing their water supplies under corporations this freshwater is locked up in the polar ice caps and that ban rain barrels, because they have contracts that say glaciers. they own the water before it falls. The UN even predicts the wars of the future will be waged over water.

Another 0.36% is found underground in aquifers and wells.

did when he called water the “blood of the Earth”.

If you do the math, bottled water costs more than the price per liter of gasoline. How can it be that something that perpetually falls from the sky costs more than something finite like oil that we are forced to drill from the ground?

Think about that for a minute.

After all, the average human drinks roughly 60,000 liters of water in a lifetime. Similarly, mature oak trees can transpire 150.000 liter of water per year!

Getting the most out of water in the garden is about more than using it as a delivery agent for fertilizers, or filtering it to remove contaminants. Water is a primary nutrient, and using form and frequency, it can be structured to be more efficient and valuable in the garden.

Water is life. It is in fact what we look for on other planets to document its presence. But a more nuanced approach to this idea would say that water facilitates life. It is the medium by which the energy of life, or “life force,” travels and communicates. In the same way sound waves cannot travel in space with no atmosphere, life waves cannot travel on Earth without water present.

Misunderstood and flowing without form, many are humbled, some are awed, but most in the modern world are unaware of the wonders of water. Some have even personified water with an agenda, as Tom Robbins wrote in his book Even Cowgirls Get the Blues, “Human beings were invented by water as a device for transporting itself from one place to another.”

Water is infused into everything that we do, even our language. We “go with the flow” when we cooperate, or “blow off steam” when we get upset. Inexperience is described as being “wet behind the ears,” and a bad mortgage is described as being “underwater.” We say these things without really even thinking about them.

My awareness of the uniqueness and the ability of water first changed when introduced to the work of the late Dr. Masaru Emoto in the film, What the Bleep Do We Know!?

The film documented Dr. Emoto’s work of showing how simple intentions through sound, emotions, and thoughts can dramatically influence the way water crystallizes.

Skeptics beware. You are free to decide that water is merely a commodity and a receptacle, and that all water is the same; or you can choose to view it as the great Water Wizard as “father of implosion theory” Viktor Schauberger

The basis of acupuncture, homeopathy, and the biodynamic methods of farming and making compost are that subtle energies can be utilized and imprinted into water and “remembered,” for lack of a better word, and can actually be manipulated and used with intention to grow healthier people, plants, and planet.

As described by Ehrenfried Pfeiffer in the preface to The Agriculture Course, Rudolf Steiner “called for a pail of water, and proceeded to show us how to apportion the horn’s contents to the water, and the correct way of stirring it… (he) was particularly concerned with demonstrating the energetic stirring, the forming of a funnel or crater, and the rapid changing of direction to make a whirlpool”.

This is the basis of the biodynamic methods of stirring BD500 and BD501 for use as what are called “field sprays.” Steiner was showing the farmers how to capture and leverage the etheric and astral forces of plants and animals in Nature, and using energized water as a tool of delivering them to the field.

Viktor Schauberger made many discoveries around the regenerative nature of implosion on water. It is the implosive moment in water where the organizational ability of water molecules becomes vulnerable and receptive to subtle energies. So when Steiner suggested the flow be reversed

in the bucket “to make a whirlpool”, rather than simply “changing directions”, he was accomplishing this implosive moment.

Intentioned growers can take advantage of this phenomenon in their gardens by using one of the vortex-style mixing machines on the market, or stirring fertilizer solutions back and forth for at least 20 minutes (Steiner instructed for an hour) in order to energize and potentize, or bring higher order and synergy amongst the ingredients.

This is how the dynamics of a meandering river work, or the life-giving energy experienced by surfers in the ocean and paddlers on a river. Think about it, compared to the efforts of dissolving oxygen with air pumps in water to grow with hydroponics or brew compost tea, one doesn’t have to aerate a river or the ocean, when given an opportunity, water seeks the form of the implosive vortex in order to regenerate and energize itself.

It is well known that water responds to celestial energies and cycles. This sensitivity in water can be seen in the influence of the moon on tides, or the age-old strategy of felling trees during the new moon when the moisture and sap are at their lowest levels. Pliny the Elder (23 – 79 AD) advised Roman farmers to pick fruit for market before the full moon, as it weighed more, but to pick fruit for their own stores at the new moon, as it would last longer.

Water is so much more capable and complex than we give it credit, so how is it that we can know so much, and at the same time, so little about something so important?

It is not for a lack of research. Dr. Gerald Pollack of the University of Washington describes in his book The 4th Phase of Water the tribulations of the history of water investigation in great detail. The Russians in the 1950s, and the French in the 1970s, both made aggressive campaigns to document the mysterious nature of water - but were rebuked in the name of “science.”

The promiscuity of water makes it near impossible to isolate pure H2O, which translates to “contamination”

in the realm of modern popular science and the scientific method. This phenomenon of water has halted almost every professional foray into the mysteries of water since the turn of the twentieth century. And here we are today.

With a more direct and nuanced understanding of water, there is enormous reservoirs of potential at our fingertips. The capacities of water speak to the efficacy of raw food, sprouting, and unpasteurized juicing. Water that is “structured” by living cells is in a different, and a more invigorated state, than the average water that we experience from the tap or bottle resulting in health and rejuvenation.

Not only is water structured by life more valuable, but it turns out that we can make it easier for water to get inside of cells as well. Peter Agre was awarded the Nobel Prize in Chemistry in 2003 for the discovery of the aquaporins. They are protein channels in the cell that regulate water, and they exist in bacteria, plants, and animal cells. In the human body alone, at least eleven different variants have been found.

The molecular structure of water determines cells’ ability to access adequate water. Basically, what Peter Agre discovered was that cells need to drink water one molecule at a time, meaning, if the structure and surface tension of water is too high we can be medically dehydrated despite the amount of water we drink, because we are simply irrigating our kidneys, not hydrating our cells. The same is true for plants.

In regards to the potentials of water in life and society - we live a filtered existence. We elicit this understanding every time we use rainwater in our gardens, invest in a water filter, or make the decision to purchase a bottle of drinking water.

So let’s take this one more energetic step further. We must inspire our imaginations towards water. We need more water conservationists and connoisseurs. Pondering the importance and mysteries of water go a long way towards levering its true potential in our gardens and in our lives. Here’s to paying more attention to our water, it does a body and a garden good. 3

Everybody knows the ironic tale of the thirsty old man lost at sea. This unfortunate chap, stuck in his boat, dying of thirst, mouth as dry as dust, is surrounded in every direction by countless gallons of water but, due to the 10,000 or so PPMs of sodium, and 19,000 PPMs of chloride inconveniently present in solution, he’s unable to satisfy his thirst with even a single salty sip!

Iron’s situation is quite similar. (It’s all too tempting to claim it’s “ironic”.) For millions of years, iron deficiency has blighted bacteria, plants, animals, and humans, and yet, it’s the fourth most abundant element in the earth’s crust. Take a soil sample from your backyard, and you’ll find iron mentioned in the lab report. So why, in the midst of all this abundance, did the World Health Organisation recently state that iron deficiency remains the most common nutritional disorder on the planet—and not just in developing countries either (www.bit.ly/WHO-iron)? In fact, over two billion people all over the world (Rodgers, et al., 2004, Velu, et al., 2014)—nearly one in three of us— are technically anaemic, largely due to a dearth of iron in our diets. So what’s going on?

In order to solve our manifold iron problem, we would do well to start with plant nutrition. Give consumable plants enough iron, especially if they end up in the parts of the plants we actually ingest, and it’s a happy domino effect from there on up the food chain. However, it’s a lot easier said than done. The key problem centres around iron’s poor solubility in soil (Carvelho and Vasconcelos, 2013).

Iron occurs naturally as goethite and hematite—both insoluble polymers (Ramimoghad, et al., 2014)—meaning plants can’t benefit from them. Iron has a positive charge, and is attracted to negatively charged clay particles in the soil as Fe3+. (Fe2+ is attached to other molecules due to the loss of an electron, and its unstable state.) Your plants’ root hairs continually pump out protons in the hope of disassociating any Fe3+ oxides, languishing on the surface of a clay particle in the soil, but it takes a whole lot of energy (and, dare I say, luck) to snatch them up (Kim and Guerinot, 2007., Hindt and Geurinot, 2012., Kobayashi and Nish, 2014).

Iron plays even more hard-to-get as soil pH rises. Adding calcium to the soil in traditional methods of liming can all

too often create lime-induced chlorosis. Apple, peach, citrus, and soybean crops often suffer in this way. The telltale sign of iron deficiency is a yellow leaf with green veins (Hindt and Geurinot, 2012). This is because iron is a key component of chlorophyll—nature’s very own solar panels—so no iron means no green colour in your leaves, and markedly reduced photosynthesis. On the other hand, if you can give your plants enough iron, then you’re essentially allowing them to “invest” in themselves.

Basically, you’re granting them a free license to produce more chlorophyll, and with it, the ability to capture more light energy.

Iron’s accessibility problems do not necessarily end in soilless, hydroponic cultivation environments.

Furthermore, it’s all too tempting for inexperienced growers to underestimate the importance of iron, as well as other so-called “trace elements”. The misguided rationale runs along the lines of—‘if plants only need, say, between 5 and 12 parts per million of iron in solution— can it really be that big a deal?’ Answer—yes indeed!

In experiments with tomatoes in NFT systems, large differences in root development were observed between plants grown in low versus high iron environments.

(Sonneveld and Voogt, 1984.) Moreover, optimal yields

were only achievable when adequate amounts of iron were present. Interestingly, the specific concentration was less in rockwool culture than in NFT, perhaps due to the increased amount of root hairs that rockwool promotes.

Hydroponic nutrient formulations use chelated forms of iron (most commonly EDTA and DTPA) to keep iron in solution. A chelate is a molecule that surrounds a metal ion and prevents it from precipitating. All sounds like a wonderful solution to our iron problem, doesn’t it? But, in reality, the use of chelating chemical agents is far from ideal.

Iron

EDTA

Chelate

To begin to understand why; imagine a ping pong ball.

That’s your iron. Next, imagine that ping pong ball grasped tightly by a six-fingered man. That’s your EDTA chelate. You ask the mutant man politely for the ping pong ball, but he’s rather attached to it, and not letting go easily. Finally, mainly due to your amazing skills of negotiation (protonic energy) you manage to persuade him to relinquish his precious ping pong ball. (Iron dissociation.) But—it’s only now that you discover that some helpful soul has deposited a small blob of glue on the tips of each of his six fingers. (EDTA’s six bonds with the iron.) So, as he tries to release the ping pong ball from one of his sticky fingers, it ends up sticking to another. Eventually you lose patience, get out your meat cleaver, and BASH! You relieve the man of both his ping pong ball and his hand. (Plant absorbing both chelate and iron.) What a palaver for just a tiny bit of iron.

It gets worse. Chelates don’t fair well under UV-sterilisation.

So, if you’re recirculating your nutrient solution and treating it with UV-C lamps, your precious iron will fall out of solution, and you’ll need to redose before feeding it to your plants again. To compound the issue even more, iron is an immobile element meaning your plants can’t simply translocate it from one of its parts to another.

A solution, a revolution even, may well be on the horizon in the form of nanotechnology. No, I’m not about to conjure up a futuristic vision of atomic-scale nano-bots working tirelessly to deliver iron to our plants. Well, not exactly. Iron oxide nanoparticles (that’s particles between 1 and 100 nanometers—a million nanometers are equal to a single millimetre. (Niar et al., 2010)) can be “wrapped” in amino acids and held in solution—allowing plants to uptake iron via simple diffusion. No energysapping, time-wasting negotiations required.

Plant response to iron oxide nanoparticles is dramatic, to say the least—lush, green foliage, super fast growth rates, shorter vegetative periods, faster fruiting, and significant yield increases. Nanonutrients are set to rewrite the rulebook for both soil and hydroponic growers—however, it is likely that only cultivators growing very high value crops will be able to justify their cost as the technology is barely out of the laboratory (Khot, et al., 2012). Keep your eyes peeled for some very interesting peer-reviewed studies in horticultural scientific journals later this year. 3

100 years ago, and 75 years ago, the UK (and the world) faced an enemy that impacted on food supply and food safety. We implemented rationing, and an unbreakable group strength to overcome these obstacles.

In the modern era, the UK and the world face a new set of common enemies; climate change, water stress, energy shortages, resource limitation, social inequalities, and societal need for healthy food.

When is it time to stop calculating risk and rewards, and just do what you know is right?

At the beginning of the year, I was chatting with Eric (Coulombe) about our interests, and some ideas for new articles. We were talking about food policies in different countries, and thought an article on UK food policy would be a good one - to see where the UK stands on social, political, and economic food policies. So, research into the subject began. The more I learnt about the food policies in the UK and globally, the less I could write on the subject, or that’s how it felt.

It was extremely disturbing to me during the research when all the facts and figures started becoming apparent, and how disproportionately everything is spread out - not just in the UK, but everywhere. So, I have U-turned on writing one article, and will split this topic into a few parts. Part I covers the facts and figures of UK food policy in the last decade to raise awareness of what’s happened, and is probably going to continue to happen if we don’t take action. Next issue in Part II, we’ll bring together the facts/figures, and try to make sense of why the UK food policy isn’t working… There’s more than likely going to be a ‘Part III’, but that will become clear as more in-depth research is carried out, and more questions need answering.

Here’s some of the questions that we’ll answer in this series, followed by the facts, figures, and stories of the people that these policies have affected, and continue to affect.

Q. What is the UK’s food industry worth, and how much do we import/export?

A. The food and drink supply chain is the UK’s single largest manufacturing sector. It accounts for 7% of GDP, employs 3.7M people, and is worth £80Bn per year.

It exported £12Bn of food and drink in 2007. Britain is not selfsufficient in food production; it imports 40% of the total food consumed, and the proportion is rising.

Q. How much does the UK consume and waste as a nation?

A. There was a rise of 4.0% in 2013 to £196 billion spent on food and drink. We wasted 7 million tonnes of food in 2010.

Q. Food security? Who is ‘food secure’, and how many are ‘food insecure’?

A. Food security: “The state of having reliable access to a sufficient quantity of affordable, nutritious food”. In 2014, more than 20 million meals were provided to people unable to provide for themselves. 1.1 million people attended food banks in 2015. This number could be higher as the cheap ready meals that are the staple of many in the UK would not qualify as ‘nutritious food’.

Q. How many people are overweight or obese, malnourished, or living in food poverty?

A. In the UK 61.7% are overweight or obese (38,460,000), and 3 million people are malnourished. Surprisingly, people that are overweight and obese can contribute to this 3 million people. This shows that the quality of food available at low prices is insufficient, or that knowledge of food, cooking, and nutrition has severely diminished over the last few decades.

More questions will appear as we answer the questions already asked, but that’s the nature of learning… The more we learn, the less we know.

I want to present a couple of facts that will hopefully make you think about the current situation in the UK, and how that makes you feel.

3.5 MILLION TONNES OF EDIBLE FOOD IS WASTED A YEAR

Q. Falling food prices, increased farming intensiveness, and a lack of sustainability - where are we going to be in 20 years?

Opinion. I am an optimist, and believe that when these issues are raised, the people will take action to prevent our situation from getting much worse. These issues will be researched for Part II. Q. Why has all this been allowed to happen, and what can we do to reverse the trend?

A. This question will hopefully be answered in the next edition of Garden Culture as we answer more questions, and dig deeper into the UK food policies.

Fact 1: Food prices have risen 18% in real terms since 2007, taking us back to the late nineties in terms of the cost of food relative to other goods.

Fact 1.1:

Median income after housing costs fell 13% between 2002 and 2013 for the poorest 10% of households.

We have 1 in 5 people living below the poverty line.

A rise in food prices is a significant problem for the poorest households, because they spend a greater proportion of their income on food. Therefore, a rise in food prices has a disproportionately large impact on money available to spend elsewhere. This could be further education, healthier food, a safe environment (heating, electricity, shelter), and other amenities that improve the overall well being of the UK’s population.

Consider a low-income household at this time of year. Do they spend the money they have on food, or extra heating to keep the family warm? If they spend it on food, do you think it’s healthy fruit and vegetables, or enough £1 frozen meals to last the week - full of sugar, fat, and chemicals?

The BMJ (British Medical Journal) published in 2015:

WE HAVE 1 IN 5 PEOPLE LIVING BELOW THE POVERTY LINE

“For the poorest in our society, up to 35% of disposable income will now be needed for food, compared to less than 9% for the wealthier. This will increase reliance on cheap, highly processed, high fat, high sugar, high salt, and calorie dense, unhealthy foods. Reemerging problems of poor public health nutrition such as rickets and malnutrition in the elderly are also causes for concern”.

(John D Middleton Vice President John R Ashton, Simon Capewell Faculty of Public Health).

Fact 2: In 2013 the UK population was 64 million, from this 61.7% were overweight or obese (38,460,000). From 19932014 the amount of overweight people went from 14.9% to 25.6%; an increase of 6.5 million people.

Fact 2.1: 500,000 individuals visited a food bank in 2015

Ugly food is wasted due to its lack of appeal in shops to the consumer. There are mountains of fruit and vegetables that go to waste, because it’s not aesthetically good enough. Policies are currently looking at how to increase food production, but we need to address the distribution of food, and the increasing food waste that would balance the scales in favour of decreasing food poverty, and improving societal health.

Actual food waste can be fed to pigs, but this was made illegal due to the foot and mouth crisis. However, there is no scientific evidence to back this up, and it needs to be researched further.

We can produce more food from our waste food, this could be the beginning of new sustainability procedures, and further our efforts to eradicate food poverty in the UK. To conclude this article, and to try to emphasise the scale of the food waste problem, ask yourselves a question; Q. Have you ever bought a sandwich from a shop?

How many of those sandwiches had a crust?

Where do all the crusts go?

with 1.1 million total visits.

Fact 2.2: Hospital admissions for malnutrition in England almost doubled in the years between 2008 and 2013. (This could be due to better screening processes.)

Fact 2.3: 7 million tonnes of food and drink (2010) is wasted every year, with more than 3.5 million tonnes of that being edible.

It’s not about saving the environment, it’s about creating an environment that doesn’t need saving… 3

GREEN PRODUCTS I GARDEN CULTURE

cool finds 1

ANNO TRELLIS A no-lean, no-rot, no-rust trellis! French designer, Frédéric Malphettes, created a configurable hanging design that works indoors or out. He used 5mm stainless steel wire to create over-sized octagon chain links that you add or remove links as needed.

Blanket a wall with vines, or create individual plant ladders hanging from the ceiling, pegs, or a frame. Made in France. Sold through ArchiExpo.com via inquiry only: www.bit.ly/chain-trellis.

2

F LOAT I N G WA L L GA R D E N As unique as Nature! The SEED planter project is the work of internationally exhibited designer, Taeg Nishimoto, a University of Texas architecture professor.

Nishimoto used crumpled Tyvek to texture concrete poured into profiles formed from river stones.The 5/16” (8mm) thick tiles appear to float on the wall, because the plant pot is attached to the back of it. In his exhibit, 2” pots (4.5cm) were used to keep them as close to the wall as possible.

More images: www.bit.ly/tn-SEED.

3

MUSHROOM LIGHTS Japanese artist, Yukio Takano, makes great use of local natural waste fashioning battery-powered LED mushroom lamps. The wiring and power source are hidden in on the bottom.

Enchanted? Many are, yet unfortunately, Takano lamps can only be had in Tokyo. But you can make one! DIY’ers on Instructables.com have easily duplicated the look substituting translucent polymer clays for Yukio’s glass caps.

Get Inspired: www.bit.ly/takano-gallery.

How To: www.bit.ly/shroom-lamps.

4

EDYN Finally! A way to make growing easier. This cool garden gadget addresses gardening challenges - anywhere.

It’s the first connected outdoor garden monitor that measures soil moisture, humidity, fertility, light, and temperature with real time reporting, alerts, and can control irrigation by dryness.

A Kickstarter project that not only turned into a reality, but Home Depot USA stocked it fast.

The campaign was wildly successful within days of launch. Looks to be out of the early adopter stage now. Check it out: www.Edyn.com.

5

AIR BONSAI

Beyond cool. The thing you never knew you must have until you’ve seen it...floating bonsai. The brainchild of Hoshinchu in Kyushu, Japan - the plants hover and rotate above a pottery base. It works through repelling magnets and balance.

Their Kickstarter page shows 6 different containers and energy bases. They raised almost 5 times their goal in just 6 days. Not a bonsai expert? Watch the How To Plant video... and grow something seasonal. Very zen!

Check it all out: www.bit.ly/air-bonsai..3

GARDENCULTUREMAGAZINE.COM

37

All the world loves bananas, indeed, it’s the 4th most valuable crop globally. Only rice, wheat, and milk trump bananas in trade. Yet, this fruit that shaped the world is a problem. Not the banana itself, but how and why an exotic fruit from the tropics became, and remains an inexpensive, seasonless staple food worldwide.

Being picked green, and gas-ripened after transport sound bad? If only that was the truly undesirable part.

BANANAS ARE CHEAP FOR A REASON, AND REPRESENT FAR-REACHING ENVIRONMENTAL, SOCIAL, ECONOMIC, AND POLITICAL ISSUES.”

THE BANANA KINGS The first tropical fruit to arrive in the North, bananas were a costly luxury, but quickly became cheap food for common folks. Normally, this happens only when an abundant crop can be grown locally with few inputs, including labor. But bananas are quite the opposite. A banana farm is a demanding thing in terms of landmass, growing inputs, and labor - yet, it’s always been one of the biggest profit-makers.

Additionally, the plants are all clones. It’s a rare seedless mutant reproducible only by division or tissue culture, which makes planting the crop much costlier than seed. They are all identical, having no diversity, no immunity to pests or disease, and transplanted divisions increases the risk of devastating infection. It’s a highly unsustainable crop threatened with extinction.

Until the 1950s all imported dessert bananas were Gros Michel. Then a Fusarium species fungus called Panama Disease wiped them all out, which cannot be eradicated from the soil once present. All growers were forced to switch to the lesser Cavendish banana. Now a second fungal disease, Black Sigatoka, has reached epidemic levels globally - and a more virulent strain of Panama Disease that spreads like the plague threatens plantations everywhere.

Bananas are cheap for a reason, and represent far-reaching environmental, social, economic, and political issues. The banana trade is, and has always been, rife with A HIGHLY subterfuge, injustices, and economic U N S USTAINABL imperialism. An in-depth accounting of CROP how this became a global staple crop T H R EATENED has all the elements of a blockbuster WITH film: violence, sex, drugs, greed, politics, EXTINCTION corruption, war, and more.

Ever heard of United Fruit? How about Standard Fruit? Sure, you have. The first company, now Chiquita, created the model for today’s globalized agriculture industry, and once commanded 80% of the banana export trade, though the original company didn’t adapt to changing world conditions. The second early banana trader is now Dole.

Between eradicating weeds, fighting pests and disease, and maintaining soil E fertility for the demanding feeders that banana plants are - over 400 agrochemicals are used. Only cotton uses more.

Some chemicals used on bananas are outlawed in Europe and North America.

Interestingly enough, the FDA reports that there are only 4 pesticides found in bananas, some suggest that the inedible peel isn’t tested. Either way, 39-57 pounds per acre applied annually is excessive! The environment, and the health of banana workers are suffering.

HEALTH & ENVIRONMENT In the 1980s, 80% of the world banana trade were held by: Chiquita, Dole, Del Monte, Fyffes, and Noboa. The first three are long established US-based corporations, while the others are relatively new to the game. Today these companies dominate only 39% due to operational repositioning.

Until just recently, your bananas came from the side of the world you lived on. Less travel ensured the import prices remained low, but now prices plummet - regardless of harvest origin.

A MONO MESS There are two types of banana growers; smallholders and the banana kings. The first use far less chemicals, require less land, and lack clout on the market. The second, transnational corporations, bring the perfect banana to market through monopoly, monoculture, and mega monocropping made possible only through using hundreds of agrochemicals, massive deforestation, environmental destruction, and social and economic control.

Pests and weeds are developing chemical immunity. Increasingly stronger pesticides, and in greater quantities, are being used.

On numerous plantations the chemical spend greatly exceed their labor costs. These massive growing operations are the result of millions of acres of deforestation, which causes soil erosion and increased flooding. The deluge of fertilizers and pesticides sinks into the soil, and runs off into the waterways, eventually spilling into the ocean.

The contaminated water is killing the fish, and polluting local water supplies, causing negative impact on the health of workers and communities around plantations. An estimated 85% of aerially applied pesticides never hit the plants, drifting over the whole area... 22-56 times a year.

“Health impacts of extensive agrochemical use are numerous, ranging from depression and respiratory problems to cancer, miscarriages and birth defects. Tens of thousands of workers left sterile by the use of a nematicide, DBCP...” -BananaLink.org

SOCIAL & ECONOMIC

AN ENTIRE COUNTRY’S ECONOMY CAN BE DESTROYED INSTANTLY WITHOUT THIS EXPORT

Currently, exporters have no control over the wholesale cost of the fruit.

Now it’s the grocers who determine where your bananas come from by price. This race to the bottom removed country of origin preferences.

The cheapest source wins, further reducing incomes for smallholders and workers.

Workers’ pay for 60-72 hours a week laboring in stifling climates over 9-12 months is based on the price their product sells for. This week, bananas are 53 cents a pound in my neighborhood, and the people who made their export possible received 10% of that, or less. And this is for the portion of the yield that is perfect; 30-40% of the harvest is an environmentally toxic farm waste, and any less than perfect fruits arriving for export sell locally for much less.

Even before supermarket chains had the power to determine the price of bananas, field workers and small producers weren’t making much money. Many already existed in poverty, unable to pay for basic living needs - and now they make less, even though their cost of living has skyrocketed. Positive social development in banana export countries is impossible. Cheap bananas have taken many lives, and only reinforce conditions that have prevailed in this industry since its birth - exploiting people, and violating human rights.

After a century of availability, bananas are an important part of nutritious food diversity that is ingrained in all cultures’ diets. It’s not like we have no options going forward - there are other sweet, edible banana varieties.

The fruits may not be so big, they may not be yellow, and the flavor is different. The banana empires have simply chosen the largest, prettiest, and heaviest bearing variety for their factory farms.

Banana workers need better working conditions, and independent trade unions to educate them what that is. Huge monoculture plantations need to be replaced with sustainable growing models that stop environmental devastation, and rebuild the soil. Smallholders have a far better model. Diversity of crops, even of banana varieties themselves is needed. And this horrible misuse of many for the benefit of a few, along with disproportionate economic and political power that rides on top of it all needs to be abolished.

How we get there is the cause of much debate. Introducing more sustainable dessert bananas to replace the Cavendish variety is long overdue. Many unknown-to-the-global-market varieties have better flavor, but Chiquita has been working on developing one for commercial production through handbreeding. Known as GCTCV 219, it’s both sweeter and better tasting, and testing of it started in Australia and Asia in 2014.

THE SOLUTION? Avoiding bananas might come to mind, but this won’t help the millions of people living in the fragile economies created by monoculture bananas. Nor would the loss of their industry to destruction by disease, which will take place, it’s only a matter of time. Chemicals are only making pathogens and pests stronger.

An entire country’s economy can be destroyed instantly without this export, the population of which is already living in poverty. This race to the bottom pricing driven by big stores like Walmart and Aldi’s is taking even that meager bit of security away. These transnational retailers are no better than the banana kings. They haven’t started a war, or overthrown a government... yet, but they’re masters at exploiting humans for profit.

Don’t boycott all bananas. There are organic and fairtrade brands available, both of which do a lot in terms of alleviating the wrongs that traditional banana growers have brought to the land, the forests, their workers, and the local population.

Yes, they cost a bit more, but fair trade bananas pay workers DIG DEEPER: higher wages, and give them · www.bit.ly/science-quarterly safer places to work under · www.bit.ly/bananas-shaped-world · www.bit.ly/Banana-Link better working conditions. · www.bit.ly/rfa-bananas Covering a topic this vast in · www.bit.ly/fairtrade-bananas so few words is impossible. · www.bit.ly/banana-chain I’ve barely scratched the sur· www.bit.ly/ethical-consumer face. 3 · www.bit.ly/tropical-race-4

Clover is a useful legume that is related to peas and beans. It also has pretty, if somewhat plain, flowers when allowed to bloom.

One of the most useful aspects of clover is its ability to pull nitrogen out of the air. As with other legumes, it can form a symbiotic relationship with host specific nitrogen fixing bacteria called rhizobia. In the case of clover, the specific bacteria is Phyllobacterium trifolii. Commercial clover seeds are often inoculated before sale to ensure the presence of the bacteria. A clover plant that has rhizobia bacteria will form root nodules. The root nodules have value, because there the bacteria can fix nitrogen directly out of the atmosphere, which it supplies to the plant.

When the clover plant dies, it can be left in place to decompose and enrich the soil, or be harvested and composted to feed to other plants. This aspect of clover is why it is known as one of the “green manure� plants, and why it is a common plant to include in crop rotations. The clover grown one season can be turned under or mowed down to help feed whatever plant is grown next in the rotation.

If for some reason a garden area won’t be used for a season, consider sprinkling some clover seeds. Mix the tiny seeds with sand to help with even coverage, and give them enough attention to get them started well. Crop rotation techniques can be used in small garden plots just as well as

large fields. Clover can also be used as a companion for taller plants, both for weed control while living, and as a nutrient source as they complete their life cycle.

Since clover makes its own nitrogen, it can be planted in areas with poor or overworked soil such as lawns to help improve them. It can be used either as an addition to existing grass lawns, or as a replacement for them. Once established, clover is more drought tolerant than grass, needs less fertilization (generally none), is aggressive enough to push out most weeds, and even comes in dwarf varieties to minimize the need for mowing. It is also a favorite of honeybees, who could use all the help they can get these days, and is even resistant to pet urine browning.

When used as a lawn, there are a few drawbacks. First of all, it is not as resistant to foot traffic as grass, which is a legitimate concern for those folks that have family rugby matches out on the front lawn, if it is to be used as a playing field, grass is probably a better choice. For the rest of us, just put some paving stones along whatever path gets worn from entering and exiting the house, and enjoy not needing to push around a lawn mower as often.

The second drawback has led to an unfair smear campaign against the noble clover mounted by the broadleaf herbicide people. Namely, that it can be killed with broadleaf herbicide weed killer. These companies even regularly advertise the effectiveness of their products against clover, as if to suggest it is something undesirable that should be killed. In other words; they make a product that kills off a drought tolerant, self-fertilizing, low maintenance lawn, in preference for water hogging, soil

depleting grass that needs mowing every week or two, and are proud enough of that to advertise the fact.

The solution to the second drawback is simple, don’t spray your lawn with broadleaf herbicides.

The third is a fair point, and it is that for best appearance, clover lawns should be reseeded more often than grass lawns. A partial solution to this is to allow the clover to flower, set seed, and supplement with additional seedings as needed. While this does incur both cost and labor, there is the savings from not buying fertilizer, mowing as often, or watering as often to consider.

Clover is one of the plants I recommend serious gardeners to familiarize themselves with, it touches on a lot of important concepts, including the sustainable fertilization of crops. 3

If you are a small or a medium indoor gardener thinking about scaling up, and building a commercial greenhouse... beware, a lack of knowledge has been revealed. From industry investors to famed consultants, very few have built a greenhouse, let alone an efficient structure with specific technology fine-tuned for a specific crop. There is a multitude of options for greenhouse manufacturers, and most are fighting for their place in line to dominate new sectors in horticulture.

With the overload of choices, charismatic salesman, and the size of this investment - you should not rely on personal knowledge of other industries. Building a greenhouse is very specific. The best approach is to hire a consultant that knows greenhouses. Knowing how to operate a greenhouse does not qualify one to design the structure or systems. For this, you need to have built greenhouses, as well as remodeled them in a multitude of situations.

The best analogy I have come up with for building a welldesigned greenhouse is the similarity to climbing Mt. Everest.

Even experienced climbers hire the Sherpa to lead the way, and help bear the load - just as your greenhouse consultant should do. It is an immense task to complete from design, licensing, and permitting to selecting equipment, and planning the budget with a reliable timeline.

Don’t slack on your Sherpa selection! They should have a track record of success, and be able to provide other happy customers as references. The consultant, when asked, should be able to tell you of a time or two where they’ve failed, and explain what was learned. None of us are perfect, and if you haven’t messed something up along the way... you haven’t done it very long. Finally, check the credentials. While a degree and work history aren’t everything, they certainly provide a solid foundation. The cost of a consultant may be expensive, but like a Sherpa, they will save you money, or even your life. And don’t be alarmed when they ask to be paid in advance (just in case you fall off the mountain along the way).

When selecting a greenhouse manufacturer, the consultant should be involved every step of the way. I have worked with many different greenhouse manufacturers, and not once have they designed a facility the way I wanted it the first time

without input. There are so many factors that go into the design. At the top of the list is preventing problems, not fixing them after they arise.

SCAL ABILITY IS THE KEY TO LONG TERM SUCCESS

The next consideration is the local environment: wind, heat, snow, hail, humidity, and light levels. Every single location is different, and the structure should reflect that.

The other obvious consideration is the crop itself. Some plants prefer it to be hot and humid, this means in a high humidity environment where a sealed greenhouse may be

necessary. Yes, a sealed greenhouse with a low amount of outside air exchange may get very hot, but with properly designed and installed cooling systems, and energy curtains - we can accomplish amazing things. The opposite is a cool, dry natural environment that will easily be duplicated in an open air flow greenhouse simply by creating air exchange. In any open air scenario, air filtration should be used to prevent insects, such as thrips.

Finally, if you are well-funded, and aspire to be a true pharmaceutical production facility, there are food safe, and

aseptic greenhouses available. The options for these extremely high tech systems run into the millions of dollars.

HOW A GREENHOUSE IS DESIGNED IS EASILY THE DIFFERENCE BETWEEN SUCCESS AND SELFDESTRUCTION

degrees variation in temperature, where more expensive integrated systems may have a plus or minus half of a degree in fluctuation.

Once you are to the point of selecting the greenhouse manufacturer, there is a high likelihood you have at least a small team of people working on the process. The greenhouse manufacturer should be an addition to the team, not the coach. Being a team player is often difficult for greenhouse manufacturers, because they have their way of doing things. They like to build what they always have, and fear change. While someone has to develop the greenhouse layout, it is a team decision. At the end of the day, the greenhouse manufacturer will build it how it is requested.

The installation and build of the actual greenhouse is a feat, in and of itself.

Something always goes wrong. This is where any design problems become reality, and have to be fixed quickly, and without slowing down the overall build in order to minimize additional expense. Very often local contractors will be used, but they will have supervision crews directly from the greenhouse manufacturer. This is standard practice, as the build itself isn’t rocket science - the hard part is in the design.

Planting density is probably the most subjective piece of the design puzzle, and every grower will have different sizes desired for plant stages, which creates complexity of the design. The main key of the layout for a facility like this is what I call a ‘single direction flow through’ design. Basically, that means a first in, first out protocol, but if the processes themselves aren’t incorporated into your design, once the greenhouse is in production mode, employees will continually be bumping into each other - creating traffic jams, lowered productivity, and potential for increased contamination.

A greenhouse manufacturer’s track record is very often their selling strategy, but this track record can be deceiving. First off, just because you have built more facilities than anyone else, doesn’t mean any of them were built properly, and building in one environment doesn’t make you able to build in opposite ones. Asking to talk with previous customers, or finding existing operators in other locations with the same greenhouse is a major step toward finding the right builder.

In the end, you want a builder who will provide true ongoing support, not just land a sale and walk away.

Scalability is the key to long term success. Most commercial greenhouses that stay in business for decades have expanded, and the most efficient designs are the easiest to scale. Literally to the point of taking down one sidewall, and adding trusses connected to new piers expands the greenhouse in one direction, and with limited disruption to production.

In closing, a greenhouse can cost anywhere between £374 and £1872 per meter square, but how it is designed is easily the difference between success and self-destruction. A builder will always try to sell you a bigger structure than you ask for. Yes, it is good for his commissions, but there is an economies of scale factor. Most structures decrease in cost per square meter once the half-acre, or one-acre size is achieved. No matter what your budget is - always tell the builder it is less. This will help anticipate the extra costs that are associated with every project, much like buying a house. Finally, have a Sherpa (consultant) that you trust with the life of your business, because in the end, he or she is your guide to glory! 3

Scalable automation creates precision in a greenhouse. It not only removes a majority of the user error, but also creates uniformity among the crops. The degree of the precision created varies widely based on the equipment selected. For example, some systems I use can have a plus or minus five

1) Kennington, South London

Urban Greening The Keeper’s Lodge at Kennington Park is buzzing with green activity. It’s the home of Bee Urban, a social enterprise doing all kinds of positive things with a focus they call “honeybee-centric.” It all started 8 years ago when London beekeeper Barnaby Shaw moved in with four hives, and some big ideas. He’s an experienced apiarist, having helped his father with his beekeeping operation as a boy, and eventually taking over.

If you’re going to keep bees, you need bee food, so they’ve transformed the outside space to provide year around forage with fruit trees, flowers, and vegetable gardens. The volunteer-powered organisation’s training center, known as the Bee Barn, was built with recycled materials. Today, Bee Urban maintains over 30 hives in 7 locations, and promotes environmental practices through education, like urban beekeeping, solar and bio digester energy, building bicycles from recycled parts, and more.

Process more valuable than the outcome.

Learn more: beeurban.org.uk

2) Inversadale, Ross-shire

Population 1000 It’s not safe to assume that people beyond big cities have space for growing food. Surprisingly, even people in tiny remote villages need allotments. Such is the case in the Scotland Highlands, where the gift of community garden space changed the lives of the residents in this crofting community a few kilometers beyond Poolewe. Even country folk want a better food source, control over how it’s grown, and environmentally friendly production.

Originally, the donated land was divided into plots for locals to grow their own produce, but the group has evolved. Their efforts have grown into something bigger. Thanks to a grant, Good For Ewe acquired some poly tunnels, making year around crops possible. They built a rainwater collection tank

for irrigation, and soon altered their production plan inside and out to dedicate space for market growing.

60 members strong and growing like a weed.

Learn more: goodforewe.org

3) Penallt, Monmouthshire

Small Ain’t Useless The idea that a 117 acre farm is too small to be useful or profitable made TV presenter Kate Humble angry - so angry, she set out to save a council farm near Monmouth from being split and developed. Mission accomplished, it became the site of the UK’s first closed-loop aquaponics system.

Conventional agriculture is definitely wrong, because Upper Meend Farm is very useful, and profitable today.

Besides the passive solar greenhouse containing the sustainable aquaponics project, there’s a lot going on here. It’s a working farm breeding sheep and cattle, doing permaculture, has a new orchard, a cafe, farm stays, and

courses on rural skills, smallholding, and food. Through Kate’s company people learn they don’t need tons of land to be more self-sustainable. The farm also boosts local economy supporting other businesses.

A very interesting place!

Learn more: humblebynature.com

4) Wester Hailes, Edinburgh

Rethinking Greenspace Council estate greenspace lawns are great for providing a spot for recreation, but they’re rethinking its purpose in this southwest Edinburgh neighborhood. Recently, the Edible Estates initiative established community gardens for residents with allotments, food hubs, and play spaces for children. It’s a collaborative effort between the Health Agency, the city, and urban design agency, Re:Solution, to increase the wellbeing of the community, and decrease maintenance costs.

The estate dwellers in Wester Hailes have really embraced this. The plots are full, growers are socially active, pitching in to help one another. It’s been such a huge success that Edible Estates is exploring opportunities to extend the program. They’re encouraging residents to set up bird boxes and wildflower plantings, and looking into providing training and jobs in intensive food production.

Awesome! Inspired by London’s Poppy Estate video on YouTube. Learn more: whee.org.uk 3

In this column Theo Tekstra discusses observations in the indoor garden culture. There is sometimes so much urban legend, and so little science in this industry. It is time to “myth bust”, and have a fresh breeze move through the industry.

Before there was YouTube, we had pure anecdotal evidence, and it was the source of many urban legends.

Anecdotal evidence is defined by Webster as “based on, or consisting of reports or observations of usually unscientific observers.” Other sources define it as “based on personal observation, case study reports, or random investigations rather than systematic scientific evaluation.”

There is nothing wrong with sharing experiences you will say, and indeed there isn’t. But to value this experience as a universal truth can be really dangerous.

it is presented in documentary format. We are easily fooled by presentation if we do not master the art of the science.

All definitions have this in common: it is usually not based on scientific methods, or presented by scientific observers. You need to ask yourself two things when reading or viewing “evidence”:

The amount of videos available on YouTube is overwhelming: for any standpoint or belief - you can find “proof” in a video.

Some productions look extremely professional, adding to the “reliability factor”. Specifically, grow trials have always been popular: different methods of cultivation (for example, different light sources) are compared, and of course, there is always a clear winner. However, if you look at those trials critically you can always see a few flaws. Let me take light as an example, as this is my expertise.

1. Is the method used to obtain this result in any way scientific?

2. Is the observer in any way a scientist?

We all know that the earth is not flat. So when someone claims it is, because he sees no curvature, it is easy to identify that as an incorrect claim. That is not so easy though, when it concerns matters that we know little about. When we seek information it is easy to be convinced by anecdotal evidence, especially if it is presented by someone we regard as reliable (whether that is true or not), or when the presentation of the evidence looks professional. For example, when supported by graphs and figures, or when

YouTube offers a great platform for anecdotal evidence.

There are all too many examples of it, and while some can easily be recognized, others seem quite legit. They are well produced, show high quality images and graphs, and the presenter looks quite knowledgeable. It’s on video, the pictures are convincing, you can see it with your own eyes, right?

With the rising of LED technology, you see a lot of comparisons against traditional HID sources. Now, both HPS and LED professional growers usually report a high yield, but in comparisons you see that one lacks substantially, even worse than you would normally expect to get as a result from that particular technology. There are many reasons why some of these results can be so different from what you see in real life, and many originate from the fact that the

grower did not base the trial on scientific methods - or used an incorrect application of the technology. Let me give you a few examples: •

•

•

•

If the yield of one of the technologies is much lower than you would normally expect, there is a flaw in the application or test method somewhere. Guaranteed.

LED, by and large, has a much more compact footprint due to the fact that it is much more directional, while HPS lighting mostly relies on overlapping fields to create a uniform lighting and more horizontal penetration of a crop. In small trials, or small square shaped trial rooms, this of course gives the LED an advantage, as the HPS fixture will spill lots of light on the walls. In a large room this effect is much smaller.

Using more, smaller HPS sources will usually give much better results in a small square room.

At lower intensities the efficiency of the light is much higher. There is not a linear relation between light intensity and photosynthesis, as with high intensities the photosynthetic rate levels off, coming close to the saturation point of the plant. However, at high intensity the yield per square meter will be higher, which can be very worthwhile, and a great investment when growing a high value crop. If you compare yield per Watt, a low light intensity grow will always win over a high intensity grow.

Scientific grow trials are always done under standard conditions. So external influences are eliminated as much as possible. When determining the efficiency of a light source you grow under similar intensity (PPFD), in an as uniform as possible field of plants and uniform lighting, and take the center of your field as the trial sample. Trials are usually small scale, so size and room factors need to be eliminated. I have seen trials done in the same room where the different sources even overlap with one another, making it impossible to get a reliable result.

•

•

Specifically comparing HPS and LED creates a problem when you give both crops the same nutrient levels.

LED-grown plants, as they get much less irradiant heat, transpire a lot less. Generally, this means that you have to up the EC of your nutrient solution substantially.

The climate in both rooms will differ, and this creates an offset. Growing under LED and HPS in the same room can actually be an advantage to the LED-grown crop, as much stray light, and specifically - heat, is added to the room, boosting the photosynthetic efficiency.

I am not saying that all of these trials are fraudulent, or meant to deceive you. Not at all. There is a serious quest in this industry to research what are the most efficient and highest quality cultivation methods, and that is a good thing. However, we do not see the same huge differences in efficiency in the many real scientific trials that are executed worldwide. LED light of the same intensity as HPS, for example, is not 30-60% more efficient as some of these trials want you to believe. In fact, there is much scientific evidence that shows that there is not a big difference in yield between the different light sources at the same intensity at all. However, with LED light you are able to distribute the light over a much more compact surface with much less wall losses, which is a definite advantage in a small room, or on a defined surface.

The moral of the story? You can not just pick and choose your evidence. There is a reason why scientific trials are scientific. 3

BY JEFF EDWARDS

54

HYDROPONICS I GARDEN CULTURE

Hydroponics, now commonly defined as the soilless growth of plants, has its root foundations in simple observations by early progressive thinkers and tinkerers. Like many scientific discoveries and their evolution to commercial application, progress came in fits and starts, with major discoveries and realizations followed by extended periods of seeming disinterest.

Many written histories of hydroponic plant cultivation methods mention the ancient Hanging Gardens of Babylon, the first written record of which dates to about 290 BC. Penned by Berossus, a Babylonian writer, priest, and astronomer, we only know of Berossus’ writings through quotes by later authors. Five primary authors, including Berossus, are responsible for what we know of the Hanging Gardens today. Their accountings were all written at a later time, based on now lost, previously written accountings by others.

Modern research questions whether the gardens were in Babylon at all, yet the premise that the gardens would in some way qualify as “hydroponic” is doubtful, based on observations by these early writers. Diodorus Siculus, writing between 60 and 30 BC, referenced the 4th century BC texts, Ctesias of Cnidus, for his description of the gardens. After detailing their construction, he includes the following passage, “...on all this again earth had been piled to a depth sufficient for the roots of the largest trees; and the ground, when leveled off, was thickly planted with trees of every kind...”

Quintus Curtius Rufus, writing in the 1st century AD, references writings of Cleitarchus, a 4th-century BC historian for Alexander the Great, who also described the “...deep layer of earth placed upon it and water used for irrigating it.” Philo of Byzantium, the author who identifies what we accept today as the Seven Wonders of the Ancient World, writing sometime around the 4th or 5th centuries AD, mentions that “...much deep soil is piled on, and then broad-leaved and especially garden trees of many varieties are planted.”

Based on these accounts alone, it seems doubtful that the Hanging Gardens of Babylon could in any way be considered soilless. In all fairness, the irrigation systems required to bring water to plantings of the reported scale, described in the form of aqueducts and water lifts, are similar in concept to irrigation methods employed today in modern hydroponic systems.

Another oft mentioned comparison to modern hydroponics in the Old World are the “floating gardens” built by the

progress came in fits and starts, with major discoveries followed by extended periods of seeming disinterest Aztecs in the 14th century AD. Arriving in the Valley of Mexico, the Aztec people found a landlocked swamp with five large lakes surrounded by volcanic mountains. For some reason, they chose to settle in swampland surrounding Lake Texcoco, and decided to build their capital city on a small island in the lake. Lacking any extra land for growth, the people started building what were essentially rectangular islands, constructed of soil, compost, and sludge from the lake bed.

Contrary to popular belief, these islands, or “chinampas”, didn’t float at all, but were rather attached to the lakebed using willow tree cuttings and a variety of materials including stones, poles, reeds, vines, and rope. Chinampas were incredibly fertile and irrigation was unnecessary since water wicked up from the lake. As many as 7 crops could be harvested in a single year due to the unique methods of composting and mulching developed by the Aztec farmers of the time. However, based on their method of construction it’s clear that the Aztec chinampas, like the Hanging Gardens of Babylon, cannot be classified as hydroponic either.

Some of the earliest recorded research into the actual reasoning behind the growth of plants, published posthumously in 1648, was written by a Flemish chemist known as Jan Baptist van Helmont (1579-1644). In fact, authorities detained van Helmont in 1634 during the Spanish Inquisition for the “crime” of studying plants and other sciences, and sentenced him to two years in prison. And while van Helmont was primarily known as the first to articulate that there are gaseous substances that differ from ordinary air, as well as introducing the word “gas” into the scientific lexicon, he is also known for a single

Jan Baptist van Helmont GARDENCULTUREMAGAZINE.COM

55

experiment he conducted using a willow tree to determine from where plants derive their mass.

This research is commonly known as “the 5-year tree experiment”…

1699: John Woodward conducted experiments growing in differing sources of water

“But I have learned by this handicraft-operation that all Vegetables do immediately, and materially proceed out of the Element of water onely. For I took an Earthen vessel, in which I put 200 pounds of Earth that had been dried in a Furnace, which I moystened with Rainwater, and I implanted therein the Trunk or Stem of a Willow Tree, weighing five pounds; and at length, five years being finished, the Tree sprung from thence, did weigh 169 pounds, and about three ounces: But I moystened the Earthen Vessel with Rain-water, or distilled water (alwayes when there was need) and it was large, and implanted into the Earth, and least the dust that flew about should be co-mingled with the Earth, I covered the lip or mouth of the Vessel with an Iron-Plate covered with Tin, and easily passable with many holes.

I computed not the weight of the leaves that fell off in the four Autumnes. At length, I again dried the Earth of the Vessell, and there were found the same two hundred pounds, wanting about two ounces. Therefore 164 pounds of Wood, Barks, and Roots, arose out of water onely.”

the differing conclusion that more than water was necessary for plant growth, and that soil was at least partly responsible for the increase in the mass and weight of plants, indicating that he too failed to clearly grasp the fundamental concepts of plant nutrition.

Unfortunately, progress in these areas of research remained stagnant until the first proper water culture experiments undertaken by a French agricultural scientist and chemist, JeanBaptiste Boussingault (1801-1887), around 1840. Boussingault had established the very first agricultural experiment station near Alsace, France four years earlier, and was responsible for a plethora of discoveries related to soil chemistry and plant nutrition. Many of his experiments involved raising plants in various soil substitutes,

Historians have deduced that the experiment was likely not an original idea, rather one motivated by Nicolaus of Cusa’s 1450 description in De Staticus Experimentis of a similar experiment that was apparently never conducted.

Further research puts the concept of the experiment back to a Greek work somewhere between 200 and 400 A.D. And while his research method is completely lacking in scientific validity, it was van Helmont’s line of inquiry and experimentation that would ultimately lead to the understanding of photosynthesis.

In 1699, John Woodward (1665-1728), an English naturalist, antiquarian, and John geologist challenged Helmont’s theoretical deductions by publishing the results of “water culture” experiments he conducted using spearmint grown in differing sources of water. His experiments showed that the spearmint grew better in water to which he added very small amounts of soil, versus “plain” water, and distilled water. His research also led him to

Woodward

including sand, ground quartz, and charcoal, which he irrigated with solutions of mineral nutrients.

Also in 1840, Boussingault’s fan and contemporary, German chemist Justus Justus Freiherr von Liebig (1803-1873), published Die organische Chemie in ihrer Anwendung auf Agricultur und Physiologie (Organic Chemistry in its Application to Agriculture and Physiology), which proffered the then ridiculous proposition that chemistry could drastically increase yields, and cut the costs associated with growing food. As a boy, Liebig had lived through “the year without a summer”, a volcanic winter event that occurred in the northern Hemisphere after the massive 1815 eruption of Mount Tambora in what is now known as Indonesia.

Near total crop losses that season led to widespread food shortages, causing a global famine, and much of Liebig’s later work towards increasing world food production was reportedly shaped by this unsettling experience.

Liebig made significant scientific contributions to agricultural chemistry, and was the first to put forth a theory on mineral nutrients, identifying as essential to plant growth the now familiar elements including nitrogen (N), phosphorus (P), and potassium (K). Interestingly, Liebig’s major downfall was his lack of experience in the practical applications of his research. One of his best known achievements was developing nitrogen-based fertilizer, arguing in the 1840’s that it was necessary to grow the best possible crops. However, he later convinced himself that there was plenty of nitrogen supplied to plants through ammonia contained in precipitation, and strongly argued against using nitrogen in fertilizers in his later years.

Despite his wavering, he is commonly known as the “father of the fertilizer industry” - not only for his identification of nitrogen and other elements as being necessary for plant growth, but also for his development of the Law of the Minimum, which observed how individual nutrient components affected crop growth.

In 1860, Ferdinand Gustav Julius von Sachs (1832-1897), a German botanist and author of Geschichte der Botanik (History of Botany) (1875), a highly regarded historical

von Liebig

chronicle of the various branches of botanical science from the mid-1500’s through 1860, published his nutrient solution formula for “water-culture”, and revived the use of this technique as the standard tool when researching plant nutritional needs. His plant nutrient formula, with only minor changes, was almost universally used for the next 8 decades.

Sachs’ experiments blazed the trail, and in rapid succession, other scientists followed up his work - the most notable of which was Johann August Ludwig Wilhelm Knop (1817-1891), a German agricultural chemist. While Sachs’ interest lies primarily with studying plant johann august processes while establishing botanical knowledge, Knop can rightfully be called the true father of water culture, as his experiments laid the foundation for what we now know today as hydroponics.

In his early experiments, Knop sprouted seeds in sand and fiber netting before transplanting the seedlings into cork stoppers with drilled holes, securing them with cotton wadding, and then suspending them in glass containers filled with solution. By doing so, Knop inadvertently established the technique most widely used for future laboratory experiments.

Julius von sachs

knop

Using this method, Knop was the first to realize that plants gain a large amount of weight simply from the food stored in their seeds, and that seeds provide nourishment to the parts of the plant that form first. By this time it had also been established that soil nutrients must be in a soluble form for plants, and that the amount of soluble nutrients in soil was miniscule compared to those that were insoluble.

These two pieces of information would form the basis for Knop’s future scientific experimentation.

What wasn’t available then were specific ways to measure these properties, such as osmotic pressure, nor did researchers of the day have any idea of what those properties might be. And while Knop deduced that nutrient solutions that were too concentrated might do more harm than good, he had no idea why.

Despite this lack of understanding, in 1860, Knop successfully grew plants, without soil, weighing many times more than their seeds and containing a larger quantity of nutrients. In 1868, other scientists using Knop’s methods, grew buckwheat weighing 4,786 times more than its original seed, and oats weighing 2,359 times more. These experiments firmly established the fact that plants can indeed be grown successfully, and productively without soil.

Over the next few decades, little effort towards developing commercial applications continued to leave the promise of water culture unfulfilled. William F. Gericke, the man who actually coined the term “hydroponics”, in his book The Complete Guide to Soilless Gardening (1940), laments the fact that “... after 1868, the conditions were as auspicious for the birth of hydroponics as they were in 1929,” the year Gericke began in earnest his research to find out if food crop production using water culture could be commercially viable.

In the next installment, we’ll explore events occurring in the 20 th century that led to the birth of hydroponics as it is known today, as well the missteps and misinformation that again led to its virtual abandonment as a practical alternative method of food production for many years to follow. 3

In an industry where dollars make sense, everyone is always looking for the next big thing. That amazing new product that gets people excited about the industry all over again. Is it possible that powder nutrients are it? It’s not like powdered nutrients are a new concept. In fact, they are the most simple, obvious, and age old ingredient in an industry that has become over conceptualized by innovation. But sometimes, when you get straight down to the root of things, less is more, and easier is better.

There are countless companies that have made an attempt to get their foot in the door in the nutrient game. Plant nutrition is an enormous industry that has the power to revolutionize our food supply, and everyone wants a piece of the proverbial pie. In hydroponics, liquid nutrients have been the standard for decades, but for growers who value efficiency, simplicity, and ease of use, powders are becoming more and more appealing, and appropriate – and here we evaluate a few of the reasons why…

Dollars. Everybody wants more of them. And powders help you save them. Whichever way you look at it, powdered nutrients are more cost effective than liquids.

It is very expensive to ship heavy bottles of liquid here and there, and powders eliminate that problem. Powders give you a lot more bang for your buck, and can finally give you more equal results than a full-on multi-bottle liquid nutrient regimen, but don’t be fooled, because not all powders are created equal.

Over time powdered nutrients have gotten somewhat of a bad rap for being too crude, incomplete, insoluble, etc., which is why liquid nutrients have always taken center stage. However, there are a few innovative companies that are changing the stigma, and coming out with powdered nutrients that are revolutionizing the industry. They are surpassing the potential of their dry predecessors, delivering high quality, easy to use formulas that threaten to make conventional feeding schedules a thing of the past.

When looking for the best powdered nutrient brand, look for one that delivers complete results. Many powders will only offer macronutrients and require numerous additives. However, there are companies that produce a well-balanced and comprehensive feeding program with one or few easy to use products.

There now exist sophisticated powder products based on plant science that offer hybridized nutrients with a high content of botanically-based ingredients

in combination with base nutrients, enzymes, and biological components. These types of powders have simplified the growing process without sacrificing the complex needs of your plants.

Powders offer consistency. Specially-micronized powders offer uniform precision in every feeding. It allows growers scalability, which is very important for growers that want to go big with less room for user error. If someone is pouring liquid from six to eight bottles, there is a lot more room for mistake versus weighing out a set amount of grams of powder. Look for a powder that is completely soluble in water, so it can be used in every medium without leaving residue, or clogging mechanical components.

Most water-based nutrients have a limited shelf life.

They lose their efficacy the longer the vital elements are suspended in their liquid medium. Liquids are also susceptible to heat and cold. Powders are not, and they have virtually no expiration. They can be stored for a very long time, and still offer the same powerful punch years down the line. As soon as the ingredients in the powder enter the water, they are activated and delivered directly to the plant roots, optimizing nutrient uptake and absorption. Liquid regiments require numerous bottles because certain elements can bond together in a liquid, leading to nutrient lockout and potential deficiencies.

Historically, powders have been associated with high levels of heavy metals and categorized as chemically “dirty” and inferior to liquids. Some of the companies producing powder nutrients today are passionate about growing, have a deep-rooted love for our industry, for plants, and the people who grow them. They are working hard to change that reputation.

We recognize the potential that this new generation of powdered nutrients offers the hydroponics and gardening industry. When you get right down to it, the proof is in the powder. 3

I hate it when people text me K, I’m very rarely in the mood to talk about Potassium via texting… I am, however, very happy to have a good chat about it now, along with Phosphorous, because P and K are very good friends in the Hydroponics industry, and it would be a shame to split them apart. We’ll start with Phosphorus…

Phosphorus is the 15th element on the periodic table with the symbol ‘P’. Due to its high reactivity, Phosphorus is never found as a free element, because it is highly reactive.

Next time you check the back of a fertiliser bottle to see what it has been combined with, you’ll usually find it’s combined with other element containing minerals. Some common Phosphorus combinations include Phosphorus pentoxide and monopotassium phosphate.

However, Phosphorus is essential to life, phosphates (compounds containing the phosphate ion PO43-) are components of DNA, RNA, and ATP, along with phospholipids, which form all cell membranes.

This importance shows in the hydroponics industry with the abundance of Phosphorus containing products in every shop, in every country. Here’s how to spot deficiencies and over fertilisation with Phosphorus…

P AND K ARE VERY GOOD FRIENDS IN THE HYDROPONICS INDUSTRY

The discovery of Phosphorus is credited to Hennig Brand, a German alchemist who attempted to create the fabled philosopher’s stone through distillation of some salts by evaporating urine. During this process, he produced a white material that glowed in the dark and burned brilliantly, it was named Phosphorus mirabilis (miracle bearer of light). And for those that love to geek out like me, the light emitted is called Cherenkov radiation. After its discovery, it was used for stage lighting during theatrical performances to light up the actors.

The first elemental Phosphorus produced was in 1669, this was white phosphorus, which emits a faint white glow when exposed to Oxygen. The faint white glow is what actually gives Phosphorus its name, originating in Greek Mythology Phosphorus means ‘light bearer’. In Latin it means ‘Lucifer’ in its reference to the morning star (Venus, and sometimes Mercury).

Although it is the 15th periodic element, it was the 13th element to be discovered. It is perhaps for this reason that it is called the devil’s element, or perhaps it’s because of its use in making explosives and nerve agents for examples of the most despicable acts known to man.

Deficiencies will manifest themselves through slow growing, weak and stunted plants, these can be dark green in colour with the older, lower leaves showing possible purple pigmentation. As Phosphorus ions are fairly mobile, Phosphorus deficiencies will initially occur in the older leaves. This is due to the necrotic tissue (dead patches), reddening of stems and poor rooting.

Toxicity will show mainly in the form of a micronutrient deficiency, with either Iron or Zinc being the first elements to be affected due to the interaction of Phosphorus ‘outcompeting’ other elements.

A ‘What is…’ article usually focuses on the individual elements, but because Phosphorus and Potassium are always found together in the PK boosting products, we’d like to include Potassium in this article of ‘What Is Are…’.

Potassium is a chemical element with the symbol K, from the neo-Latin ‘Kalium’ and has the atomic number 19. You may remember it as the soft silvery metal that reacted vigorously with water in school. I remember it as the silvery metal that destroyed the school’s toilet when we

decided we wanted to see what a bigger piece of potassium did… The chemistry teacher was impressed, the headmaster not so much. The equation for that toilet water reaction was as follows; 2K + 2H20 = 2KOH +H2 It was first isolated from Potash (the ashes of plants), which is where it also gets its name. Humphrey Davy was the scientist that is credited with finding Potassium in 1807 from caustic potash (KOH – Potassium hydroxide).

IF YOUR PL ANTS BECOME POTASSIUM DEFICIENT THEY BECOME SENSITIVE TO DISEASE INFESTATION, AND FRUIT YIELD/ QUALIT Y WILL BE REDUCED

Potassium is involved in maintaining the water regulation of the plant, the turgor pressure of its cells, and the opening closing of its stomata. It is also required for the accumulation and translocation of newly formed carbohydrates.

If your plants become Potassium deficient they become sensitive to disease infestation, and fruit yield/quality will be reduced. Older leaves will look as though they have been burned along the edges, a deficiency known as scorch, because Potassium is mobile in plants.

If you add too much potassium the plant will become deficient in Magnesium, and possibly Calcium due to this imbalance, with Magnesium deficiency likely to occur first. There are good arguments for the use of a Calcium/Magnesium supplement during flowering periods of heavy PK use. We will be looking at this in more detail with Garden Culture’s next edition of ‘What Is Are... Calcium and Magnesium’.

There are two topics that you might think we’ve missed in this article of ‘What Is…’ - the relationship of P and K in flowering additives, and the impending Phosphorus crisis. Both topics require an article by themselves, so that gives you something to look forward to or fall asleep to…

Thank you for taking the time to learn a little more about Phosphorus and Potassium. But before I go, here’s one to finish: Did you hear about the time Oxygen and Potassium went on a date? It went OK… No more, I promise. 3

Flowering plants (Angios pe

rms) use seeds (usually)

tion. Seeds are an amaz ing answer to some pret

as a means of reproduc-

ty formidable problems.

In many parts of the country, the killing cold of early winter brings an end to the life of many annual plants. When temperatures drop below freezing, expanding ice crystals burst tender cell walls. For some it is a swift death with the first few frosts, for others the end of post-flowering decline, and still others struggle on until finally succumbing to the icy grip of cold. In order for the species to survive, there has to be some way for the plant’s DNA to be preserved past the life of the parent plant - for weeks, perhaps months, until conditions improve.

Plants are notoriously “rooted in place,� inhibiting their personal mobility. The ability to package tiny plants into small containers allows for the use of wind, water, animals, or people as carriers to expand their territory beyond the physical reach of the parent plant.

Seeds solve both these problems by being a tiny plant (embryo) packaged with enough food to get started with (endosperm), and secured inside a protective covering (seed coat).

In plants that produce seeds; male flowers produce pollen on their anthers that when applied to stigmas of female flowers can fertilize the ovule. The pollinated ovule forms a zygote, which grows into a tiny plant

(embryo). The embryo will already have seed leaves (cotyledons), stem (hypocotyl), and a root (radicle), and be encased in a shell (seed coat). The shell helps to protect the small plant, and allow it to go into stasis until it finds itself in conditions conducive to sprouting.

Food stores (endosperm) may be inside the seed coat, or outside it as is common in fruits.

To help the tiny plants inside seeds stay in a state of suspended animation, excess moisture is allowed to evaporate as the seeds dry out.

Depending on the type of plant and conditions, the seeds may last through winter, or other harsh weather, to sprout in the spring or they may last for several years.

Seeds kept too wet may sprout prematurely and then die, so seeds should be kept in a dry container at cool temperatures for best storage.

(micropyles). This moisture will cause the plant to swell, and soften the seed coat, allowing the radicle to break through using hydraulic pressure to seek more moisture, and the seed leaves to swell and open to seek out light.

One way to help with getting moisture through the micropyle, is to soak the seeds in water for 24 hours.

Another is known as “scarification” helps to weaken the seed coat, and allow the plant easier access to moisture.

This involves nicking the seed coat with a sharp object, or rubbing the seed on a rough surface, such as sandpaper or an emery board.

most seeds should not be soaked i n wat e r fo r d a y s on end

Germination often starts with the reintroduction of moisture to the seed, and ends when the plant ends its reliance on the food stores, and can draw nutrition from the environment. The requirements for germination are moisture, oxygen, an appropriate temperature, and for some plants, light. The seeds of most plants have a low moisture content, which helps them have a long “shelf life.”

Before a seed will sprout, it must first be rehydrated.

When the seed comes into contact with moisture, it draws in the water through a small (relatively small, they can be easily seen on coconuts for example) holes

Moistening a paper towel, wringing it out, and putting it with seeds in a plastic bag in a warm location to sprout is another way to aid moisture in saturating the seed.

If using this method, change the paper towel every few days to keep it fresh, as it is an environment conducive to germinating plant seeds, but mold spores as well.

Once a seed becomes waterlogged, fungus can set in and ruin it.

The amount of oxygen needed by a particular type of plant varies. Some plants will not germinate even in the presence of moisture, unless air is also present. For this reason, most seeds should not be soaked directly in water for days on end, but transferred to a betteraerated environment after an initial day or so.

Moist seeds will germinate at a temperature of 68°-86°F (20-30°C), with 75°F (24°C) being ideal for many plants. In cold settings, a heating pad may be used to raise the temperature of seed trays.

Some seeds germinate better in light, and others in dark conditions. Check the information about the type of seed to learn which it prefers.

It i s common to start seeds indoors 6-8 weeks b e fo r e t h e last frost d at e

Many seeds can be sprouted by simply burying them 3 to 4 times their width, and kept moist, but not soggy, until sprouting. To prevent the media from drying out too quickly, sometimes domes or plastic sheets are used to keep the humidity high while seeds sprout. However, do not allow the seedlings to stay too wet for too long, or fungus may start to grow on the plant near the media, causing the fatal condition known as “damping off.” Media should be “moist” - not “wet.” Do not allow the media to dry out too much, however, as once the plant has germinated, it loses its ability to survive without water, and with such a small root system, it can quickly dry out and die.

Quality harvests depend on quality seeds, whether purchased, gifted, or gathered. Seeds from many plants can be collected, and used the following year. If the seeds are going to be collected, for predictable results “open pollinated” varieties should be used. These seeds will tend to produce similar plants from one year to the next.

In late winter to early spring, it is common to start seeds indoors to be prepared for spring planting.

To determine when to start your outdoor garden seeds indoors, find out the date of the last frost in your area. Then read the seed packet, which should tell you how many weeks before the last frost date to start them.

Some plants have an additional concern when calculating their planting dates, photoperiodism, which means that they use the duration of their dark periods to determine when to flower. Spring and fall both have longer nights than the short nights of summer. These plants bulk up during the summer, until the longer nights of fall trigger flower, or fruit set. The reason that this can be a concern, is that if these plants are set outside in the spring months when the nights are long, they can immediately begin flowering.

Depending on your area and need, it is common to start seeds indoors 6-8 weeks before the last frost date.

Plants started indoors should be “hardened” by moving to a sheltered location, or gradually increasing the time the plant spends outdoors. This allows the plant to become used to the new conditions over time, and minimizes the shock from the change.

Starting plants from seeds can be rewarding, and cheaper than purchasing established plants. As an additional bonus, starting seeds indoors can extend the gardening activity months. 3

Rooting cuttings is a time honored tradition that allows for certain plants to be propagated asexually. It effectively allows the same plant to be grown in multiple pots. Since the new plant shares the same DNA as the parent plant (barring mutation) it is commonly referred to by the term “clone�. Cavendish bananas are all clones of the same plant, most wine and table grapes are clones, so are practically all potatoes, and the grafts for commercial fruits and citrus.

Cuttings are generally taken during the most vigorous part of the plant’s growth cycle, but before flowering starts.

Since the parent and the cuttings share the same DNA, they will be the same genotype, if grown under similar conditions, that will tend to express as similar phenotypes (the directly observable attributes of the plant). So a cutting from a yellow flowered plant will also have yellow flowers, and a cutting from a female plant will also be female. This can be used to good effect when a lot of the same color flower is desired in varieties that have a variety of colored flowers.

This method of propagation can also be used when determining gender, as a cutting can be taken, and exposed to a flowering light schedule while the parent is left under growth lighting (or vice versa). Whatever gender the parent shows will also identify the gender of the others. Clones can be useful to propagate a number of plants with the same characteristics, such as when a roomful of relatively identical yellow flowered female plants is desired.

Cuttings from plants grown from cuttings have the same DNA as the original plant. Usually, anyway, if the original

group of cells that formed the branch that the cutting has been taken from were mutated, then the branch may be of a different genotype than the rest of the plant, and cuttings taken from that branch will also be different from the rest of the plant (but the same as other cuttings from the affected branch).

Cuttings are able to form roots from stems and growth nodes by using a type of plant cell known as a meristem cell. These are undifferentiated cells that can mature into a variety of adult cells depending on the environment that they are exposed to. The growth tips in plants have so many meristem cells in them that they are known as shoot apical meristems. The meristem cells in the growth tips mature into shoot and flower cells, adding to branch length, leaf development, flowers, and fruits depending on which type of cell is called for.

Another high concentration of meristem cells can be found in the root tips, which are also known as root apical meristems, which mostly mature into root cells.

It is important to note that the meristem cells found in the growth tips, along the stem, and in the roots, are all exactly the same, and it is the conditions around them that determine what they eventually develop into.

Indolebutyric acid or naphtha lene ac etic acid encourage root development

Grafting is basically taking a cutting and placing it into a matching cut in a rootstock plant. The meristem cells in this case grow to heal the cut. This may be done to match superior rootstocks with superior fruiting varieties, or as in the case of citrus, seed grown trees may take 10 years to mature enough to grow fruit, but a cutting from an existing older tree grafted onto fresh rootstock can produce fruit in a couple years. This is because the cutting and resulting growth from the graft is already old enough to produce fruit.

Meristem cells are also critical when using tissue culture techniques, as their ability to mature into any type of adult cell can be manipulated into making a complete plant from a tiny cutting.

For a normal cutting to be grown into a complete plant, it should include a shoot apical meristem (growth tip, or at least a budding site) and a section of stem. It is the meristem cells in the stem and any lower budding sites that are induced to develop into root cells, and create new root tips.

When taking cuttings from a plant, the cut should be neat and clean, as it will make a wound in the parent plant. To

prevent the cutting from suffering from terminal wilt (which will kill it), keep the cut end in water until it is ready to be used.

Before putting in the rooting medium the ends of the cuttings can be exposed to a plant auxin hormone, such as indolebutyric acid (IBA) or naphthaleneacetic acid (NAA), to encourage root development. Both are frequently applied in the form of a rooting powder, gel, or liquid.

The stem end of the cutting is placed into a mild potting soil, oxygenated water, or other suitable medium in a warm location under moderately bright lighting. If a solid medium is used, it should be kept moist, but not soggy. If over watered, the end of the stem may develop a fungal infection and rot. Under favorable conditions, roots will generally appear within a week or two, although some plants like tomatoes can root within a few days, and some plants may take a month or more. As long as the shoot portion of the plant is kept healthy, and there is no indication of root rot, the chance still exists for a particular cutting to form roots eventually.

Rooting cuttings is mostly a matter of getting conditions right, and perseverance. Some plants root easier than others, but being able to propagate asexually via cuttings is a handy tool to add to a gardener’s skillset. 3

In the series “Light Matters�, Theo Tekstra discusses different aspects to lighting, such as quantity, quality, efficacy, special applications, new developments, and the science behind it. In this first episode we focus on quantity. How much light do you give your plants? And how does that matter?

Plants are Photon Counters Plants use photon strikes for the synthesis of chemical energy, such as sugars. I say strikes, and not light energy, because it is the number of photons that is primarily responsible for the process, and not the individual varying energy of those photons. Blue photons for example, contain a much higher amount of energy. That extra energy, however, is mostly dissipated into heat. To bind a CO2 molecule, you need about 8-12 photons. So, you see it is a numbers game! We need to know how many photons hit our plants to get an idea of the total potential photosynthesis.

Plants are photon counters. Look at photons as rain drops: the lighter the rain, the less water reaches the surface. It’s the same for light: the fewer the photons, the less light plants get for photosynthesis.

Counting Light To quantify grow light, we first need to establish which photons to count, and how to express that in numbers.

It has been established that photons with a wavelength ranging from 400 nm (blue) to 700 nm (red) contribute most to the photosynthetic process. That is why we call photons in this range Photosynthetic Active Radiation, or PAR for short.

In order to quantify a stream of particles, we need to count how many reach the surface, at a given time, on a standard size surface. The international standards for time and surface are second and square meter. Taking this back to raindrops again: the rate of the raindrops is defined by the number of raindrops that fall on a square meter of surface in one second. It gives you the density of the rain.

The same applies to light: the intensity of the (photosynthetic) light is defined by the PAR photons

reaching a surface of a square meter every second.

This is called Photosynthetic Photon Flux Density, or PPFD. Unfortunately, photons are so numerous that that would easily lead to a 20 digit number, which is a bit hard to read and value. There is, however, a standard unit of measurements which defines a large number of particles such as atoms, molecules, electrons, and photons. It is the mole. By all means, if you want to learn more about moles, take a look at Wikipedia, but for now, it is enough to know that 1 mole of light is 6.22 x 10 23 (the Avogadro number) photons.

The notation for mole is mol, just like ‘s’ is for second, and ‘m’ is for meter. As we already saw light intensity is Photosynthetic Photon Flux Density, which is moles of light per square meter per second. The scientific notation of “per square meter per second” is “m -2 s -1” - so for space’s sake, and to make it look real scientific, we are going to use mol m -2 s -1 from now.

Full Sunlight at midday is about 0.0025 mol m -2 s -1, or 2.5 millimol m -2 s -1, or 2,500 micromol (µmol) m -2 s -1.

I think you will agree with me that the µmol m -2 s -1 is the easiest to use here. Which is fortunate, because this is the way we measure the photosynthetic photon flux density.

To recap: • Photons are so numerous that we count them in moles of photons.

• Photosynthetic Active Radiation (PAR) is defined in the range between 400 nm light (blue) and 700 nm (red).

• Light intensity is defined as the number of PAR photons per square meter per seconds, so mol m -2 s -1. In practice, we use µmol m -2 s -1.

Amount of Light Per Day A light rainfall that continues for 20 hours can result in much more water than a short heavy shower. There is a relationship in the intensity of the rain, the length of the shower, and the amount of water that reaches the ground.

The same goes for light: the total amount of photons reaching your crop is based on the intensity of the light, and the light period. The intensity, or PPFD, is defined as mol m-2 s-1, so by multiplying this by the number of seconds to get this intensity per day, you get the number of photons per day, expressed in mol m-2 d-1 (moles per day). This is the DLI - ‘daily light integral’.

Q: So basically for a higher yield, I should just give more light?

Let’s work on an example.

- PPDF is 1000 µmol m-2 s-1 - Light period daily is 12 hours in a 24 hour cycle

Here is a graph representing the three limiting factors:

A: Yes, but there is an optimal and maximum amount of light per day, and also a maximum intensity you can give your plant. A shade plant, for example, can only take a limited intensity, and short day plants do have a maximum intensity and DLI. It is also a function of what we call the limiting factors for photosynthesis: - Light - Carbon Dioxide - Temperature

To convert PPFD to DLI, multiply by the number of seconds you are lighting your crop: 1000 (µmol m-2 s-1) x 12 (hours) x 3600 (seconds per hour) = 43,200,000 µmol m-2 d-1, or 43.2 mol m-2 d-1.

And there you have it. The relationship between the light intensity, and the amount of light per day.

Questions and Answers Armed with this information, let’s try to answer the following questions: Q: If I give half the intensity of light, and double the time the plants get it, does that have the same effect on photosynthesis?

A: Yes, it does. This is how we light tomatoes and roses in greenhouses. They are long day plants (which flower and fruit when there are long days of light), and they get up to 20 hours of light per day on dark days. However, if you are flowering short day plants (which flower when the nights are long), there is a limited period of about 12 hours in which you can give that to your plants. So, in that case, you will use a higher PPFD to get the same DLI in a shorter period.

These three have to be in a balance. When there are one or two too low, it will cause the plant to perform sub-optimally, and there are absolute maximum and optimal levels as well.

So more light might require a higher temperature, and/ or more CO2. It is the grower’s mission to find the right balance for his crop, and this is just one of the balances.

Other factors are the climate (as in humidity, for example), available water, and nutrients.

Q: What is the optimal PPFD to give my crop in an indoor environment?

A: For that you need to know the photosynthetic response curve of your plant, and you need to make a choice whether you want to harvest as much crop per invested energy (grams per Watt), or crop per square meter (grams per square meter). It requires an experienced grower to do the last, as you will be growing up to your plant’s limits.

Let me explain this with a diagram, showing photosynthesis (Pn) against irradiation (I) of a specific crop (for other crops this may be different). A second variable in this graph is temperature:

MORE LIGHT MIGHT REQUIRE A HIGHER TEMPERATURE, AND/OR MORE CO 2 At low intensity, you see a more linear increase of photosynthesis when the light intensity increases.

However, with increased light levels, at some point the photosynthesis tapers off, and at a certain level may even cause photoinhibition. So doubling the amount of light does not automatically mean that you will have double the amount of yield. For every temperature, there is a saturation point: a point where adding more light will no longer add to extra photosynthesis. The saturation point is lower at a high temperature, but the efficiency of the applied light is much higher at an optimal temperature. Hence, you need to grow at the right temperature to get optimum effect from your light, 30°C in this example.

Q: How about supplemental lighting in greenhouses? How much do I need?

A: That depends on the DLI of the sunlight throughout the season you grow, and your crop. The DLI you get from natural sunlight depends on your geographical position.

Purdue University published a good overview of DLI during different seasons in the USA:

Remember the limiting factors of photosynthesis? The moment you see the curve tapering off, you have reached a limiting factor. In this case, temperature and PPFD were variable, while CO2 is a constant. Adding CO2 will give you a longer linear curve, so a much higher photosynthetic rate.

Q: Should I use the same PPFD during the vegetative stage of my short day crop?

A: Using the same PPFD in the vegetative and flowering phase will result in your crop getting 50% more light (higher DLI) in the vegetative phase when you light it 18 hours in veg, and 12 hours in flowering. Reducing your PPFD in veg by 33% will result in the same DLI. So, if you flower with 1000 µmol m-2 s-1 for 12 hours, giving your crop 667 µmol m-2 s-1 for 18 hours will result in the same amount of light per day.

Source: http://bit.ly/purdue-DLI

However, that is not the DLI your crop will receive in the greenhouse: • During a clear sky summer day of full sun you will probably shade your plants, because the PPFD is too high, reducing the DLI of the sunlight.

• Your greenhouse construction takes away light.

Transmission losses can be as high as 25%, or more.

Secondly, you need to know the optimal DLI for your crop, and whether you are going to give this in a long day, or a short day. For a short day crop, the time that you can light your crop is limited. The light level will need to be higher than for a long day crop, which you can light for a long time to compensate low sunlight DLI. 3