Did you know you can regrow spring onions? Even those you buy from the store?
When you cut them, leave the roots and about 1-2cm of the white stalk. Pop them into a container with a little bit of water making sure the stem is out of the water. In a few days the onion should start to grow again. Once you have some growth, pop them in some soil - either a pot or the garden is fine - and water in well. Keep it watered and in about a month the spring onion should be ready to harvest again.
