Yes, We Can. Just think, why we need soil for the Plants to grow ? Its very clear that the soil plays an important role in holding the plant . The roots of plant lays in Soil and supplies minerals and water from soil to the plant. You know well that not all types of soils are suitable for any plant. Some where the land is barren and some where its more fertile. The fertility of land depends upon the availability of types and quantity of minerals in its soil as well as the pH of the soil i.e. availability of H+ or OH- ions when its wet.
Now it is possible to grow plants without soil, if we can hold the Plant and can supply minerals to the root of growing plant. Now a days different researches have been done and many are in progress. So, we may use soil less light weight material like COCOPIT, PERLITE, CLAY BALLS, FOAM etc to hold the plants. Its advantage is that these materials don’t have free minerals in them so, we can provide minerals to the plant through roots in water from outside. So, a major advantage is that if we know what kind of minerals and in which ratio are required by the particular plant, we may supply the same.
As you know in 1951 we were 361,088,090 * i.e. around 36 crore (298,644,381 rural and 62,443,709 urban) . I have taken these data from the Government site Census of India . Today we are more than 1,361,088,090 . It means about 100 crore people increased in number while, the agriculture land is relatively reducing . As per the World bank data of 2018 Only 60% land is available for cultivation and agriculture purpose . Day by day the area of agriculture land is reducing while population is increasing.
My dear friend you and me are living in the era of Economy (आर्थिक युग) . No body care about your health except yourself, if the money come in-between. As you know if farmer don’t use pesticides etc. his vegetable production will come to the bottom. So, You just Give up hope that someone will feed you vegetables without pesticides. The only way is Just grow vegetables at home by yourself, may be on roof top, now or later.
1. Due to physical weight of Soil, Forbidden to use for gardening and growing vegetables on the terrace.
2. there is Lack of Water availability in urban area and also ground water is going down. Soil consumes more water due to evaporation and drainage while in hydroponic system water runs in closed pipes and is recycled. So, only evaporates through plant leaves and there is no drainage like wastage of water.