Green onions do not need to be refrigerated.
But if you want to refrigerate green onions the refrigeration helps keep the green onions fresher and makes the green onions last longer.
However although you do not have to refrigerate green onions if you do refrigerate the green onions they stay fresher longer.
To refrigerate the green onions place the green onions in a jar with a bit of water in the jar and then cover them with a plastic bag and store them in the refrigerator.
The green onions should keep for a few weeks to a month in the refrigerator but it's best to eat the green onions before they lose their freshness.