Blog GHE hydroponic systems fertilizers bioponics

By Noucetta Kehdi – GHE

Saving water and fertilizers, eliminating go-betweens and long distance shipping, and increasing good quality food production are becoming major issues that hydroponics can easily address. Everywhere, and especially in big towns and cities, you see sprouting vertical farms, urban gardens, vegetal walls, community and family hydroponic farms, and auto-production. With more people getting attracted by the advantages and applications of hydroponics, the question of organic hydroponics naturally came to mind, and this is what we call “bioponics”. Simply said, bioponics brings “soil”, or rather what is contained in soil, to hydroponics: not only nutrition, but also life. Simpler said than done, as you might imagine. It took William Texier, the inventor of bioponics in 2004, many years to create the adapted nutrient, and put together a concept that actually works.

Is bioponics possible? Could you really combine the water saving benefits of hydroponics with a sustainable organic nutrient program? How can the essential microbiology be maintained in an aqueous hydroponic environment? These questions often arise, as this technology is new and yet attractive. Some keep their doubts, but we also receive regular testimonies from horticulturists who went for it, and love their results.

How does it all work?

We now know that plants feed with mineral salts in the form of electrically charged ions wherever they grow. In hydroponics we feed them with an exhaustive formula of mineral salts in the form of ions dissolved with oxygen, immediately available for absorption. In soil, food is provided by mechanical crushing, breaking, and dissolving of rocks, sand, etc, and by biological decomposition of organic matter by micro organisms, releasing particles and liberating ions that plants can absorb.

To be suited for hydroponics, a nutrient must be precisely designed, comprehensive, liquid, and fully soluble. In hydroponics indeed, it is imperative that a complete diet be immediately available for absorption, and that the irrigation system remains clear for optimal oxygenation of the nutritive solution. A traditional organic nutrient for soil generally consists of large molecules at different stages of decomposition. With time it becomes fermented, may smell bad, and will always end up clogging your circulation.

The concept of bioponics is to reproduce, in water and soilless substrates, appropriate growing conditions for plants, in a way to those that exist in soil; in other words rebuild a viable microcosm where plants can live and develop. To do so you need a well aerated, highly oxygenated hydroponic system, a bioponics nutrient, and Trichoderma harzianum, a fungus specialized in decomposing organic matter. Your objective – and challenge – is to create a synergy between each element, to generate and sustain a new life cycle with its transformation processes.

How to start bioponics?
The first key factor : the adequate nutrient

A dynamic hydroponic system, with strong circulation and a dynamic flow is a very important factor in bioponics. High levels of oxygen will benefit your plants of course, as well as the microorganisms that are living there. The choice of system is also important because the substrate it includes will determine the way to care for your microorganisms, as we shall see below.

But more important, in fact the first key factor without which bioponics would be impossible, is the nutrient. All nutrients are not suited for bioponics, even if they are organic, and even when they are certified. Indeed, a bioponic nutrient has to be manufactured with elements derived from certified organic sources (to respond to regulations and obtain a certification). It must be precise, exhaustive, liquid, and highly soluble. It is a complex combination of already dissolved ions from organic origin, and larger organic molecules that will decompose rapidly (in a couple of days), to guarantee continuous nutrition availability from instant one. This fast decomposition process is activated and sustained by the introduction of a special microorganism in the system, a fungus that feeds on the carbon part of organic molecules and releases the ions attached to them, which is exactly what plants are looking for.

Along with the nutrient you may use a series of organic liquid and highly soluble supplements as various sugars, amino acids, humates, etc, which will enhance taste, aroma, and production.

Second key factor: the microorganisms

While a bioponic nutrient is very soluble, there still remain particles that must be decomposed. And this is the role of Trichoderma harzianum, the easiest to find and
most efficient microorganism for this use. It is a fungus, extremely active and easy to handle:
• It produces highly efficient enzymes that dissolve organic matter,
• It releases mineral salts essential for plant life
• It induces systemic resistance to plant disease by colonizing the plants roots,
• It competes with, and parasites pathogens like pythium, fusarium, etc.
• It also has a great advantage for us “hydroponicist”: it likes the same pH ranges that are essential for our plants, between 5.5 and 6.5!

Trichoderma harzianum, along with many other microbes, exist naturally in a good earth. But if your soil is dry, poor, brittle, or just depleted, it is recommended to add these little organisms along with your fertilizers to make it richer and more productive. In a hydroponic system you have to add them yourself of course, and depending on the substrate you are using, you’ll have to adapt the environment to their needs.

To develop and multiply, Trichoderma need to live in an environment that is clean, aerated, rather warm, well oxygenated, and wet at all times! All substrates don’t apply to this use, or not so well. There are three main categories commonly used in hydroponics: water-retaining substrates like coconut fiber or rock wool, draining substrates like lava rock, perlite, or clay pebbles, and … no substrate at all, like in bare roots systems.

In rock wool or coconut fiber there should be no problem: just add them to your mix, they will live happily and thrive, providing they have immediate access to food. Clay pebbles, perlite and lava rocks are draining substrates: they won’t retain enough humidity. In this case, we mix 10 to 20% coconut fiber with the pebbles before adding them into the system. Trichoderma will establish in the coconut fiber, and the clay pebbles will keep the environment well aerated.

Good to know:
Lately we discovered a new brand of clay pebbles, quite large, extremely rugged and very porous, where Trichoderma live and reproduce without coconut fiber. Our experiments were particularly successful, and we now recommend their use in hydroponics as well as in bioponics.

Now, when you are growing in aero-hydroponics, with only a few clay pebbles and/or only water as a substrate, breeding Trichoderma becomes impossible without the proper breeding grounds. We use a “biofiltre”, a device you can build yourself or buy ready-made. Bio-filters are generally used to clean wastewaters or polluted air, and are perfectly adapted to bioponics. They are made up of a container, a mechanical filter to retain debris and keep your circulation flowing (a sponge can do), and a substrate for the fungi to establish in (we use a porous synthetic rock in the form of little stars, others might use lava rocks for instance).

You can also buy a filter for aquariums in any pet store, and add your own substrate and fungi. Or you can buy them ready-made for bioponics. Biofilters are an absolute imperative in the “aero versions” of hydroponic systems, but growers use them with “hydro versions” as well, because they are reliable and efficient. You can also breed other fungi and bacteria in your biofilter, depending on the result you are looking for. *

 

* Have you heard about mixes of organisms that live in biofiltres? Those mixes often contain Trichoderma harzianum along with other fungi and bacteria. They are a little expensive compared to Trichoderma, and would be an overkill if used only to decompose organic matter. We use them to protect root systems during high temperatures, a task better adapted to their cost!

Preferably avoid placing your biofilter in line, because it will slow the circulation. Suspend it inside the reservoir and let the water intake connection hang into the solution. Connect it to its own electrical source to keep it on even if the growing unit is at a standstill (at night for instance). Contrary to prior information, do not add silicate into the tank as it will interfere with microorganism health. And don’t forget, Trichoderma like it wet and well oxygenated all the time. If dry they’ll die! Place your sponge and the stars into the biofilter, sprinkle with microorganisms. Every 6 to 8 weeks replenish with new fungi as the natural lifecycle declines with time, so regular additions are always beneficial.

In the proper environment, and with plentiful food, Trichoderma will reproduce and develop naturally. At this point it is important to be aware of a singular phenomenon: Trichoderma harzianum, like many living things, prefer a stable environment. Avoid extreme swings in oxygen, temperature, humidity, nutrition, pH levels, over population, etc…A large quantity of dead Trichoderma could result in low pH. So if you notice a sudden drop in your pH level, check your fungi, which may have suffered from stressful conditions. At that point identify the problem, fix it of course, and eventually replace your nutritive solution before seeding again with new organisms.

Third key point:
How to manage a bioponic nutritive solution?

Like for hydroponics, bioponics is a fast car you drive by sight, with a long-term vision, prevention and anticipation being your primary tools. You’ll also use EC and pH meters, but not the way you were accustomed to: understanding the process that develops in a bioponic environment is another key factor.

Electro-conductivity (EC):
Although exhaustive, an organic formula will not show the same readings for EC and pH as a mineral nutrient. Indeed, organic molecules don’t carry electric charges, and therefore are not recognized by your EC meter. When you dilute your nutrient in the water, only a small fraction is immediately dissolved and transformed into ions, giving very little conductivity. The rest will be decomposed later.
So, to avoid over-feeding, the idea is to add your nutrient progressively, in small quantities, for two or three days. While nutritive elements are liberated, others will be absorbed by the plant, and conductivity will tend to remain in balance around the same values. When the stock of organic matter becomes insufficient, EC will drop. It is time to add nutrient again.

Bioponics in a private greenhouse in Germany

pH levels:
An organic nutrient cannot contain (by regulation) the buffers you find in a good mineral nutrient, which specialize in stabilizing pH levels. During cultivation, you might notice a tendency for the level to rise. But pH is not as essential in bioponics as in hydroponics. Plants will accept ranges going from 5 to 7 without problems, and you don’t need to adjust constantly. Just avoid extremes, and when you use regulators, use them at homeopathic dose, making sure they are diluted long before they reach your Trichoderma.

Happy growers:

Once you secure nutrient and microorganisms, and you know how to handle both factors correctly in a soilless environment, there is not much else to do. Of course, as usual, provide your plants with the adequate environment: proper light, temperature, humidity, ventilation, etc. Make sure your system is clear for free circulation and high oxygenation of nutritive solution. Keep a good eye, and apply prevention.

The concept of bioponics, although still new, is expanding by the day. Many projects are developing in different countries:
• An organic tomato farm in Saint Barthélémy (West Indies): to serve restaurants and hotels with fresh home-made products in this highly touristic island, Mr. Hervé Meunier started his small hydroponic farm in 2008, using biponics. The small structure he started with became today a profitable greenhouse operation, able to serve an increasing number of clients with organic produce.
• In Germany Christian dedicated his small hydroponic greenhouse to growing greens, vegetable, and his collection plants with both methods: organic nutrients on one side, and minerals on the other. Both with equal success and pleasure. A diaporama of his work will soon be posted on our blog. Have a look.
• Since last year, in Holland, biponics is used on a larger scale by a company who tests products for the greenhouse industry. Their results growing salads are so good that they decided to promote the technology to their clients. More info will follow.
• In France several new companies are building vegetal walls for indoors as well as outdoors home decoration. They often use a bioponic nutrient as some of their clients are inclined to use organic instead of mineral. (see mursvegetaux.com – in French).

These projects were brought to our attention through enthusiastic testimonies. Many more must exist which we know nothing about. The only downside I see to bioponics is when you are a commercial producer and want to certify your crop as organic. The organic certification agencies, in France anyways, won’t give you an organic certification for a “bioponic” produce, even if you grew it with a certified organic nutrient, and that’s because there is no soil in hydroponics … Double Bonus, our client from Saint Barthélémy, did not try to get it: he advertises his crop as grown organically in hydroponics, because apart from the fact that he has no certification, he is using a low water consuming technology, producing on the island high quality fresh foods which would have otherwise been imported from faraway regions, therefore past their best, and expensive. He is creating jobs in a country where they are extremely wanted, and participating in the economy of his island.

Combining hydroponics and organic growing techniques is the best of two worlds. Growing hydroponically allows you to cultivate plants under any latitude with reduced amounts of nutrients and water. Using a closed circuit, it prevents mineral salts from leaching into the ground water. It promotes larger yields in reduced areas, helps produce good quality food in highly populated areas, and reduces shipping costs and pollution. Based on the principles of sustainable organic agriculture, bioponics uses very little nitrate thus reducing tremendously the biomass while favoring flowering and fruiting. This consequently induces more water and nutrient savings, even higher than in traditional hydroponics!

Researching Internet about bioponics, I found some references and a few blogs. Evidently the information is not very wide spread yet! Some will call “bioponics” growing plants in symbiosis with fish. This technique is generally called aquaponics, and although quite close, doesn’t use the same process. In bioponics we do not add fish, and aquaponics do not use nutriments apart from fish effluents. I also saw other references for bioponics as we understand it under the name of Dr. Luther Thomas in Utah. It seems that he, and William Texier in France, came to the same conclusions more or less at the same time, which shows that great ideas have no frontiers!