A live plant is great, but you still have to feed your Fish. Give him special Beta pellets.
Carrie, I never heard of Betas living in shoals. I know that you should never put two Males together, because they fight until death. A Male and Female is ok. My Beta was giving to me in a large Vase with a live Plant. After a few months he moved in to a 50 gal. Tank. I think he is much happier and gets along just great with all the other Fish.