Yes, vegetables can be grown in water,the method is called Hydroponics.
Hydroponics is an advanced technology in Agriculture which makes agriculture possible everywhere!
It is a soil-less farming method where plants are grown in a controlled environment in nutrient-filled water. It is a particularly useful method in areas that have poor soil quality.
Leafy vegetables like lettuce, spinach, cabbage, basil, chives, papaya, strawberries, watercress, rosemary, potatoes and flowers are some popular crops grown using Hydroponics technique.
Vine crops like tomatoes, cucumber, peas grow well too, but require adequate vertical support.
One of the key benefits of hydroponic farming is the fact that it uses only those nutrients that the plant needs to grow. It minimises water wastage and ensures that water is applied directly to the roots. Further, this system ensures minimum fertiliser wastage. It also cuts out the risk of weeds, pests and diseases, particularly those associated with soil.
With hydroponic farming, out of season crops can also be grown, since cultivation is done in controlled environment in greenhouses.
In India too cultiver are using the technique of hydrophonics for profitable agri business of exotic vegetables in organic culture in a huge commercial way.