By Salim David
Hydroponics is not a new concept. In ancient times, the plants lining the walls of the Hanging Gardens of Babylon were grown using hydroponics. Only over the last century, however, has it gained popularity as a method of commercial cultivation, mainly in the West. It is now in the early stages of becoming popular in India as well.
Hydroponics recognises that soil is not necessary to grow the best plants. Here plants only thrive on water, sunlight, air and nutrients.
Hydroponics, where ponics is derived from the Greek “ponos” which means labour, literally says that water works for you. And so it does! The plant’s root is kept in an enclosed area where the water (with dissolved nutrients) bathes it regularly at 15 minute intervals for five minutes at a time (this may vary) — allowing the root to get adequate water while getting sufficient air as well. In some crops the root is left floating in the air. In other cases where the plant is large and the root needs stability, the root is loosely anchored in a sterile medium such as rockwool, coconut fibre or similar medium.
Unlike conventional soil farming, there is no wastage of nutrients in the hydroponic system. Every gram of nutrient is dispensed in the correct proportion, depending on the age of the plant. It goes straight to the root and then back to the tank to be fortified for the next round of offering. Not one ounce of nutrient is wasted nor is one drop of water given up (barring some natural evaporation despite the covers on the roots).
Compared to soil irrigation, the water saving is 90 per cent and nutrient saving is likely to be 35 per cent. (In soil irrigation, a substantial amount of nutrient is wasted on the weeds around the plant, while some nutrients percolate below the reach of the root as well.)
No weeds also save the labour spent in weeding. This is a huge saving, not to mention that weeding is a cumbersome and back-breaking job.
The absence of soil also precludes all soil-borne pests and fungal diseases, saving on treatment and, in turn, resulting in a healthier, larger and more productive plant. The complete cover of the greenhouse also ensures that even the smallest pest cannot get into the growing area. Double doors for entry of farm personnel, a discipline of washing one’s hands in sanitised solution, are further precautions in creating a pest-free and germ-free atmosphere.
Hydroponics has been a gamechanger in the West. India could be looking at a paradigm shift as hydroponics solves the dual problem of yield and water availability most farmers face. The yield with hydroponics is 5 to 12 times as high as soil farming. This is possible with the nutrient targeting and precision as well as controlled conditions of light, air and sanitation.
Studies have shown that micronutrients have a great impact on the taste and health benefits of the crop. Simply put, one micronutrient may reduce bitterness, another increase the anti-oxidant property of the food on offer. Hydroponics controls the distribution of the nutrient every 15 minutes as it pumps water with the appropriate nutrient with this regularity. In soil cultivation the nutrient is put once a day, if drip irrigated, otherwise once a month! There is little scope, in soil cultivation, to micromanage the nutrient, which is now seen as key to getting growth and quality.
Let’s look at what India is faced with. For one, small landholdings – an average of two acres or so, and diminishing every generation as land gets divided among sons. Then there are non-scientific agriculture practices with the use of heavy chemical fertilisers and pesticides. Land fertility depletes and yields are at all time lows. The consumer suffers due to high levels of pesticide, which is akin to poison.
The vicious circle of poverty and debt prevails for the farmer as his average income from the two acres averages Rs 12,000 to Rs 20,000 per month, but can become negative every other year due to crop failure (due to the farmer’s lack of knowledge sometimes) or water shortage. The farmer’s challenge is increasing returns per acre. It is an axiom in agriculture that the more care and complexity a crop requires, the more return it gives the farmer.
Hydroponics requires care and precision to get the required results. In growing exotic crops, quality is paramount and is a critical factor for getting the best price. To take advantage of the best plant advice world-wide, hydroponic companies are often permanently connected on whatsapp and email to a central agronomist who has a fixed routine of diagnosis and treatment of all plants under his care. Hydroponic companies often take the responsibility of not only growing the crop(s) but also ensuring the route to market and best prices.
One hydroponic farmer recalls an occasion where he mentioned to the Spanish agronomist that the cherry tomatoes in one site had lost their customary sweetness. The agronomist prescribed an addition to the nutrient mix, and in 12 hours the sweetness was restored!
Net profit in hydroponics, if supervised appropriately, could be in excess of Rs 4 lakh per month/per acre, and this has been documented.
It’s time we adopted hydroponics on a large scale. A few state governments have already shown interest and are keen to extend the greenhouse subsidy to hydroponic equipment. Not only for yield or quality improvement, but also where soil quality is depleted or water is scarce, hydroponics can enable profitable and sustainable agriculture.
Enough of testing the waters … it’s time to dive in!
(Salim David hung up his corporate boots some years ago and now grows roses and organic vegetables near Hyderabad. The views expressed are personal. He can be contacted at [email protected])