hydroponics FAQ

What is hydroponics ?

Hydro-What ?? We face a lot of different reactions when we tell people that we grow plants in a hydroponics greenhouse. Most don’t have a clue about it, some have a bad opinion, others think we grow banned plants …! Yet hydroponics is not new ! It was used by the greatest civilizations : Incas, Aztecs and in the famous hanging gardens of Babylon. Why ? Because it has many assets !

The principle is simple : it is to grow plants by replacing the soil with an inert substrate or with water, like us. In this water, we will add mineral nutrients, organic matter and oxygen. The roots float happily in this water and can absorb easily all the ions that we put at their disposal. Everything works in closed circuit recirculated by a pump.

What are the benefits of Hydroponics ?

The benefits are numerous. Here are some examples :

  1. It makes it possible to grow plants where a ground culture is impossible, such as in an arid environment, on polluted soils or in urban areas.
  2. Thanks to closed circuit, we save up to 95% water compared to land farming.
  3. Access to water makes the work of the farmer more complexe. We constantly have to check if our roots have enough “to eat”, in good quantity, if  the oxygen is sufficient, if the pH is ideal for absorption of nutrients… In hydroponics, we give the plant exactly what it needs for its good development, no more nor less.
  4. This last point makes our plants absolutely delicious, if you are sceptical, come and have a look in our greenhouse, we would be happy to let you taste our products and appreciate their flavor. This will change your perspective about an erroneous idea that circulates: “hydroponics gives vegetables without flavor”.
  5. Soil protection: the entire nutrient solution provided to the plant is absorbed, nothing is lost in the soil, so there is no risk of groundwater pollution.
  6. We do not use herbicide, that’s obvious.
  7. As part of our project we do not use any pesticides, but it’s quite easy because our plants grow fast and healthy, and are therefore more resistant to pest attacks.
  8. It is very ergonomic, you can install systems at ground level to facilitate the work of the farmer.
  9. Hydroponics allow the control of many factors that are impossible to control in soil. Thus without deficiency, the plant can express all its genetic potential. This is also a great revelation for medicinal plants because the active ingredients of plants grown in hydroponics are much more concentrated than on the same plant grown in the ground.
  10. If the conditions are ideal, the yield will be greater than soil culture’s yield. Also the systems allow easier crop rotation.
    Hydroponics, when properly used, completely changes the way we see plants grow. It’s an experience you have to try, see and taste.

And finally :

No soil = no weeds

Are you trying to replace the soil ?

Not at all ! If you have a good land, we will always advise you to exploit it !
Our vision is to allow agriculture where the land is not exploitable. This is mainly the case in arid environments (many project leaders come from Africa to follow our training programs), in a polluted environment, or in an urban environment. Hydroponics can never replace the soil, but it can be a good complement. We find this technique very brilliant and seek to improve it (see the research section) so that it can be used responsibly.

Hydroponics and ecology ?

Since 2013, we have worked everyday on many aspects to make the commercialisation of hydroponics as ecological as possible. We are emphasizing on commercial hydroponics as it is very easy to do something sustainable on a domestic system. However, for hydroponics to develop, there is no secret : the ecological and environmentally friendly processes can’t impede the productivity. Indeed a company not profitable, even with the best values of the word, will not succeed. That’s the whole challenge !

– Soil pollution:

For years, for”hygiene” reasons (careful, this is a very controversial debate) the nutrient solution use to circulate in open circuit, meaning leaving the tank to feed the roots, and then going directly into the wild. This was causing a terrible mess and pollution of groundwater. The solution, too concentrated, imbalances the micro-bacterial life of the soil. Therefore, in our case, we recirculate non stop the solution in our system. Nothing is released in the nature and nothing is spoiled as the ions “wander” until they are absorbed. It also allows us to have EC concentrations (electroconductivity) much lower and to have a bacterial life in our system, our best ally!

– Energy balance:

We hardly use water, same for electricity.  Indeed our experience has allowed us to put in place techniques to maintain a minimal electricity bill. We do not use lamps or heating… This remains greenhouse culture, but we consume 500 x less kW per m2 than in a greenhouse of tomatoes (yes, yes, we made the calculation!).

– Growing medium :

Instead of throwing away and redeeming everything, we have developed techniques to clean all our growing mediums without the use of chemicals. Then we reuse them all ! #zerowaste !

– Phytosanitary :

As mentionned before, we don’t treat our plants. No phytosanitary treatment, no organic treatment, no grandma’s magic potion. Nicolas is very strict about this ! Our experience is to let nature do without influencing it. You would be very surprised by the results, the losses are minimal and intrigue many market gardeners. The greenhouse is wide open and insects arrange between them. It is a fascinating sight to watch.

– Systems maintenance :

In traditional systems it is common to use hydrochloric acid or nitric acid to clean. Well, with us, as you can imagine, no chemical disinfection ! We clean everything with water and sun ! Of course, there are still things to improve but we are moving in the right direction and for us this is what is most important.


– Origin of the nutrient solution :

See the next section where everything is explained! It is certain, there are still things to improve but we are moving in the right direction and for us this is what is most important.

What is the difference between hydroponics, bioponics and aquaponics ?

The techniques are very similar, it’s all about feeding the plant with a nutrient solution. The origin of the nutrient solution will define its membership in one of these three categories.

In traditional hydroponics :

Only mineral nutrients, in the form of ions, are added to the water. So directly assimilated by the roots of plants, it is simple, effective and healthy. Don’t be afraid of the term “minerals” because it is the same thing found in mineral water for example calcium, potassium, magnesium …. There are on average 16 elements with the carbon, oxygen, hydrogen that are present everywhere in the air and in the water. The problem with traditional hydroponics is that minerals, although not dangerous to health, come from mines. And for some this resource is limited. It is therefore on the ecological factor that it can be a problem. Hence the development of the other two categories:

In Bioponics :

We do not use mineral nutrients, only organic nutrients. Plants do not know how to assimilate molecules, so we have to add a biofilter to the system and do everything for the development of bacteria. Because it is this which transforms the organic molecules into ions, then assimilated by plants. Organic nutrients can be made “home” (compost tea bags, purines …). But it is difficult to measure precisely the presence and the quantity of each of the elements necessary for the growth of the plant. We can also find some in the trade (for example we use BioSevia of GHE.). In all cases Bioponie represents for us the logical evolution to conventional hydroponics. But it is not yet developed enough and the results that we obtain are not sufficient to be able to live it commercially. That’s why we participate in a research program on the subject.

In Aquaponics :

It’s even more complex: Fish droppings are used as a base for plant nutrition. So we produce both fish and plants. And as in biopony, fish droppings are organic molecules, so not directly assimilable by plants. So you have to add bacteria to do this job. There are 3 worlds to manage (with three different physio-chemical needs otherwise it would not be funny!). The world of plants, the world of bacteria and the world of fish. The next time you come across an aquaponic grower tip him your hat. To understand everything: Fish droppings provide mainly nitrogen and a little phosphate, not much in the end. But according to the food given to the fish, its quality, its composition, we can count on it to bring other organic and/or mineral elements. And despite that, if you do not add anything else to the nutrient solution, it may appear deficient, which is not a problem if you are an individual, but on a large scale it is critical. It is then often provided supplements in organic form (purines, biosevia …) and / or mineral (this is the case of pH adjusters such as calcium and potassium, iron, trace elements) directly in water or foliar spray. on the plant.

Is it organic ?

We practice what we call sustainable agriculture. Which means we face the same challenges as organic farming, but the Bio label applies only to earthen crops. We are committed to using sustainable and responsible cultivation methods, we do not use pesticides or herbicides. We favour biological control to defend our plants against attacks of insect pests. The water we use is recovered and recycled, our green waste is composted, we deliver our products on the day of harvest and to order to avoid waste. We favour plant breeds based on their taste and not on their resistance to transport. To counter an uneconomic import of species imported from Asia that arrive depleted from transport, we offer restaurateurs the same plants freshly harvested that we produce locally. Offering tasty and healthy food is our priority.

Is it lucrative ?

This is probably the most frequently asked question we get by email! Nicolas and I manage to live on our farm, the rest of the income we get from the training we offer allows us to stop during winter, to do buildings to ameliorate the greenhouse… But for us, it is possible to live out of farming.

After I often say that even if hydroponics and urban agriculture is “trendy”, it’s still agriculture, it’s not the “good plan” to become very rich very quickly! Then it really depends on everyone, its location, its business strategy. I am unable to guarantee financial profitability! As with any business, you need to find a good niche to meet an existing need. During our training in hydroponics, a whole chapter is dedicated to providing you with tips for achieving financial profitability.

How much do I have to invest ?

Again, I do not have the magic answer that everyone would like to hear! It’s a complex question, because it depends on many factors! It’s like asking us the price of a house, it’s too variable! In our case, our hydroponic greenhouse is voluntarily rather low-tech: we rent the structure, we do not use lamps, heating or CO2 injectors, … So our investment cost and fixed costs are very low. By contrast, if we imagine a greenhouse on a roof, fully automated, the investment price will be 10 times higher than ours! The best is to draw several possibilities according to its project, and for each of the possibilities try to find the economic balance. During our hydroponics training we share our investment costs, and a whole list of suppliers who can help you define prices and build your business plan.

What grows in hydroponics ?

Surprise : everything can grow in hydroponics ! Plants we have seen grow in hydroponics and aquaponics include: trees, cacti, succulents, root crops – all plants can adapt to water. On the other hand, it will be necessary to find the system and the mode of irrigation adapted for each of them. For example, the cactus will prefer a rather draining growing method with watering on a timer just a few minutes a day. And if it is for a commercial enterprise, it is also necessary to take into account: What is profitable in hydroponics. I do not know about fruit trees, but I imagine that to make apples in hydroponics we will spend on electricity, water and nutrients for years before starting to harvest. While in the land the costs associated with this growing method are rather low! It’s a calculation to do. Generally the plants that are most produced in hydroponics are leafy vegetables such as lettuce, aromatic plants and some vegetables such as tomatoes, peppers, eggplants.

Can we move a plant from the ground to hydroponics or vice versa ?

Without any problem ! The water roots are a little different from the roots of the earth, so it takes a little time to adapt. But it is quite possible to pass a hydroponic plant to the ground. And to pass a plant from the ground to hydroponics is even simpler.
I even made a short (french) video about it: https://youtu.be/b530qMvb0jM

Is it savoury ?

When I hear “hydroponics, it tastes like water” it bristles my hair ! A terrible belief due to tasteless tomatoes, which grow, certainly in hydroponics, but very different from ours! The taste of a plant will depend on several factors: – The variety of the plant And yes, the tomatoes of the supermarket have no taste because they were selected for their resistance to transport and their longevity on the stall instead of being selected for their taste! Our tomatoes of ancient varieties are sublime and delicious. But they only spend a week at home after being harvested. – The moment of harvest Nothing can replace the sun, it is he who will gorge the sugar plant. So by growing seasonal products and harvesting them very ripe, we are certain that their taste will be at their maximum potential.

It’s clear, it’s frustrating to eat tomatoes only between June and October. But we prefer to eat (and sell) delicious tomatoes over a shorter period of time than to sell a tomato that will have sprouted in March under a lamp ! In addition (a very personal opinion) it becomes a pleasure to wait for a tomato salivating for several months. The wait increases the pleasure of seeing them blush very slowly on their tomato stem. Then in August, we abundantly harvest them and we make tons of jars to keep all winter. It’s a new way of experiencing the seasons. -The plant nutrition.:

We are what we eat.

Well for the plants it’s the same, if we give them an incomplete nutrition, they do not feed us either. Our strategy is to invest a lot in the nutrition of the plant to have products of super quality taste. In addition to having a delightful taste, it makes them healthier and stronger. Only a sick or deficient plant will attract insects or diseases. Feeding our plants allows us not to need to treat, with phytosanitary nor with organic treatment. It’s simple, we do not put anything on the plants (Nico is very tyrannical with this concept). Conclusion: If the culture is well conducted, giving good nutrients to the plants, choosing the varieties well, and harvesting them well mature in season. So a plant growing in hydroponics can be as good (see in some cases better) than a plant that has grown in the ground. If you’re skeptical, I can understand, come take a tasting tour in our greenhouse. No-one ever left disappointed!

I am looking to settle in hydroponics / aquaponics, where to start ?

Well first, congratulations for this initiative !!! There is room for everyone and we would really like more people to get started. There are many things to discover! And more project leaders will be interested in the subject, the more the whole industry will grow! My first tip is to start small, because everything we learn about 1m2 will serve on 10m2 and 100m2. So start with a small homemade system on a terrace, a balcony, or in your living room! Especially do not invest a lot, it is possible to do DIY for almost nothing. During our initiation to hydroponics, we make together 2 small very simple systems! The idea is to start to confront the technical details, understand the basic operation, and especially to live the pleasure of your first homemade harvest! A priceless experience. Then you can follow tutorials on youtube (my favorite learning platform!) And read simple books about hydroponics like “Hydroponics for Everybody, All about Home Horticulture ” by William Texier.

Get help !

When you want to move to a professional level, it is wise to be followed by institutionnal organizations !  It is also wise to do your market research, evaluate the installation costs, and start looking at what it’s like to run a commercial hydroponic or aquaponic business.

Can I come visit your greenhouse

Yes, absolutely, the greenhouse can be visited, but not anytime! We like to share our knowledge, but as long as we can give you quality time, and time is something that is critical for us. In any case I do not advise you to come to the greenhouse without warning, because it is not our land. The owner does not tolerate unaccompanied persons on his private property and you will be “kindly” escorted out. In addition put yourself in our shoes, falling on unexpected strangers in your workplace, even with the best will in the world, it’s never pleasant ! (Sorry but it’s history!)

Two options, to visit the GreenHouse :

– During training, this is really the best option because the aquatic garden is yours for 2 days, and all our time is dedicated to you: to be at your disposal, inform you and answer all your questions.

– We organise half day long events of guided tour, usually during Summer. You can find the schedule online on our website. Tarif : 5 euros per person

– If you are a group / association / school : contact us by email, we can organize a tour. Group feed : 50e

Tours can be explained in French, English or Spanish!

Follow us on our very frenchy social media to be the first to know about our next events : Facebook , Twitter , Instagram & Youtube !

You can also watch our F.A.Q video (in French – currently working on subtitles !)  we made for our 5000 followers on YouTube (may 2018)