So i bought an onion from walmart and one day i noticed that an onion i had sitting in a basket in the kitchen started sprouting long green leaves. I decided to plant it in my backyard with no prior knowledge of gardening (i live in florida btw terrible sandy soil) after a few weeks its growing really well. Now im wondering how can i get more bulbs from just one onion. Will it sprout more bulbs? Seeds? Just cutting it in half and planting both halves? How do i produce more?