When I first joined Pinterest, I came across this awesome experiment on how to keep your green onions fresh and continue to grow, just in your kitchen. I realized every time I bought green onions, we would never use them quite enough to keep them from going bad.
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.