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How to Grow Onion Bulbs in a Glass of Water

By Peter Timm

Growing onion bulbs in a glass of water is a great way to extend the usefulness of your onion. Instead of using your onion as an ingredient for only one meal, you can re-grow several times -- if the onion is cooperating. All you need is a glass of water and the lower half of a green onion bulb. Re-growing your onions can give you a maximum use from a single vegetable, using the green onion tops to flavor your recipes.

Cut off the bottom of your green onion, leaving approximately 1 inch from the bottom. When you cut your onion, leave the small roots on the bottom of the bulb intact.

Fill your glass or dish with enough water to cover the roots of the bulb. Place the bulb into the water with the roots down and the top emerging over the surface of the water.

Place the glass in a location where it will receive lots of sunlight, such as a windowsill. Keep the bulb supplied with water and allow it to grow for approximate two weeks. At that time, you may cut off the growth and repeat the process.


Things You Will Need

  • Small glass or dish
  • Knife
  • Green onion

About the Author


Peter Timm has been writing since 2002 for both print and online publications. Timm earned a Bachelor of Arts from the New York Institute of Technology in 2008 and emerged a technically astute writer.