Most people seem to believe that plant gets nutrients from soil through roots.
However, what I found out was - it is not just through roots.
Plants can absorb nutrients from soil through it's stems and leaves too. If stem is in contact with soil, it will absorb nutrients from that soil. Stem of a plant has openings capable of absorbing nutrients.
This can be easily observed. I noticed that plant grows much better if you keep adding soil around its stem so that it is in contact with that added soil. In fact, burying a stem with an inch of soil around it while plant is little does so much for the plant. It grows much faster from the start.
The added soil must be loose.
The process is very simple. After a little plant grows 2 inches, add 1 inch of loose soil around its stem.
As plant grows, keep adding soil but dont bury the plant too much. At most, it should be 6 inches of soil in total after the plant is big.