This experiment comes from Homemade Serenity. There are a lot of neat experiments and DIY's on the blog. So for these green onions/scallions, I actually buy mine at the store/Farmer's Market. When I come home I immediately put them in a jar of water. Every other day, I clean the roots and give them fresh water.
As you can see, they grow pretty fast! Now I need to find me some recipes that call for green onions.