Winter is a good time to start lemon grass plant indoor. First, you must select a lemon grass from a grocery store that has main bulb or root bulb intact like the ones shown on photo below.
Fill a clean flower vase with tap water halfway and put the bulbs in. Put the vase with the lemon grass in a well lighted area preferably under a bright fluorescent light. It will take almost all winter months for the roots to grow. Change the water in the flower vase every week. Rooting solution is not necessary for the roots to grow, just make sure there is sufficient water in the flower vase until the weather is warm enough to transplant it in a flower pot and put outside. After the roots grow, some leaves will follow. The leaves might be pale and wispy due to absence of sunlight but it does not take long for lemon grass to grow thick leaves once it is planted outside when the weather is good and warm.
I immensely enjoyed my lemon grass that I started indoor and I had abundant harvest and plenty to give away to friends! See how the bulbs turned green on photos below?
One thing I would not do related to lemon grass is – I would not plant it in the ground. It is a very tough plant to dig out! It is best to plant it in small to medium size flower pot that can be easily taken inside during Winter. It cannot be left outside because it cannot survive cold weather.
This is a very easy plant to grow but watch out for those razor sharp leaves!