To understand the commercial aspects of food in our country you need to first understand how hydroponics emerged in the first place. The concept of water culture was devloped in early 1950s probably by the Americans to cultivate food in places where there is no soil like space, extra terrestrial planets like Mars, Moon, etc.
So, hydroponics is required to suffice the hunger of astronauts in space as they cannot carry tons of soil, water, fertilizers along with them in their space shuttle which will increase the fuel expenditures. Hydroponics happens to be the most efficient way to cultivate food with minimal resources and leaves zero residues.
Hydroponics is now used in countries with extreme weather conditions like high frost or high temperatures with arid and sandy soils. Not even a blade of grass can grow on their soils in this extreme weather conditions so they use technologies like polyhouse, isolated rooms and artificial weather control for growing food. If these countries start importing their 3 square meals of food from other countries it will impact their economy, food is basic necessity and without it no country can be a healthy nation so, they have no go and they need to produce food in their country to reduce import taxes on food. For example, Dubai has severe water shortage issue but, they have no problem of energy, they can cultivate vegetables using hydroponics in many acres of land using air conditioners can an Indian farmer afford that?
So let's come to scenario of India, we have many fertile soils, our tropical climate is moderate, we have very few cases of water shortage compared to other countries and agriculture is in the DNA of each and every Indian, if we trace back to atleast 5 or 6 generations back, our ancestors would have directly or indirectly involved in agriculture activites for their livelihood. Agriculture also forms about 20% of our GDP involving exports and domestic consumption.
So, using hydroponics can we really compete with the market prices of vegetables which are sold today? When I speak vegetables it's only leafy greens because leafy greens can be stacked vertically in less space we get more produce, other bigger vegetables like tomatoes, peppers, etc., can be grown but the same space saving may not be possible as they occupy same space either on soil or hydroponics.
Hydroponics as claimed by many people say that it saves 90% of water, but what are the prevailing conditions which make the production of plants with less than 90% water? These include temprature, humidity and proper carbon dioxide in the air surrounding the plant, right illumination, proper water temperature, dissolved oxygen level in water, right pH, right TDS and the list goes on for a commercial scale. The water to be used in active hydroponics or true water culture should be only RO water, we very well know that to get a glass of RO water we waste atleast 2.5 glasses of water, so where exactly is the point of water saving here. Cold countries have ample amounts of snow available freely on road which they can conveniently melt to water and use directly but that's not the case in India.
So, it's not like I put a hydroponic system in open environment and expect the same water efficiency in summer and winter. Not every farmer in the country can afford to the whopping ?6 million polyhouse with artificial weather and illumination control just for leafy greens. Even if he does, by what time can he achieve his break even point?
Remember, we are comparing this with traditional soil farming and we are citing reasons why we should shift to hydroponics. Soil farming does not involve all such costs at all. A farmer broadcasts the seeds of leafy greens on his farm and hardly waters it, within 30 days he has his produce ready because he is not aiming at flowering and fruiting stages of plants, leaves would however grow for a plant because of its natural biological cycle, there is no much effort required to grow leaves. This holds true even for exotics like lettuce, kale and broccoli which are grown in our hill station areas like ooty and Kodaikanal. Same technique is used but, why are the prices high? To maintain cold chain and transport prices increase. Many people don't even know that we can use soil and simple temprature control techniques to cultivate the 30 day lettuce in any place and it's extremely cheaper when compared to the whopping hydroponic setup costs which are typically ?12 million per acre including polyhouse.
The major part which each and every commercial hydroponic grower ignores is about nutrients. For a home grower any nutrient can be used because he is not bothered about the quantity of yield, he is only interested in reliability of the system. Whereas, for a commercial grower who has about 100,000 plants, a tiny increment of 1 gram per each plant can fetch him an additional 100 kgs of produce so, nutrients have to be chosen carefully.
Many people think and few people cheat their customers by saying that nutrients sold by them are suitable for all green leafy vegetables. How is it even possible? A Kashmiri person's dietary requirements may not be the same as that of a South Indian person though both are homo sapiens. Then how come we can use same nutrients for spinach, mint, coriander, lettuce, etc., which are completely different plant species? Even if we talk about spinach, there are so many other sub species of spinach which will again have different nutrient formulations. For a typical green leafy vegetable we have three stages namely sapling, mild vegetative and fast vegetative growth which are given in phased manner.
In soil farming, roots, bacteria and fungi help each other in choosing the required nutrients for plant from the pool of soil but, hydroponics is something where we need to know the hunger requirements of a plant and supply accordingly. You give less the plant won't grow properly and you give more the plant may die or not grow properly again. It's like balanced nutrition for plants which enables high yields. All this can be done only by a crop scientist who knows the correct experimental techniques, correct research design and who has appropriate experience in dealing with this before from a reputed organisation. People like BSc or MSc agriculture students are not useful as they have no exposure to any such experimental techniques or how to choose a research design, a specific crop scientist makes the experimental time less and has had access to many scientific journals and crop related publications compared to latter people.
Again, nutrients are dependent on the type of system, so there is a non linear relationship between expense for the type of system, expense for nutrients, profits from sales and many other factors to be considered, why? Because we are competing with traditional farming and want better margins than it so all this analysis is compulsory at commerical scale or else, every businessman will have a nightmare if his break even point extends days to weeks to months.
Pioneer nations who developed hydroponics like Israel, America, Canada, etc., have their own research and methodologies which will cost higher amounts of money to be shared with us. So, commercial hydroponics in India as I can say is not the requirement of hour as it involves many parameters.
But, hydroponics can benefit urban home growers as they seek reliability, it is more in hydroponics compared to organic or soil as we know what are the nutrients supplied and the media like coco peat doesn't grow weeds. So, for the busy urban people who don't want to spend time on removing weeds, applying pesticides it's a comfortable option for them as they don't have time but the same is not true for a commercial grower as he is involved in the profession. Even home growers don't need sophisticated hydroponic equipment, they can use the Biryani containers or small pots filled with coco peat and comfortably grow greens throughout the year with very minimal expenses.