Regrow Spring Onions in Water – Fun Gardening Hack

Growing onions is a pretty easy from a gardening standpoint, but did you know that you can also regrow spring onions in water?

At times like these, when some food items are in short supply, knowing how to get more bang for your buck is a win in anyone’s book! Using parts of an onion to grow them again is a real bargain.

This gardening hack is one that kids will love to help out with. Children are normally quite impatient, but spring onions regrow very quickly so they won’t have to wait for results!

If you use a lot of onions in your recipes, you will also want to check out my post on growing onions indoors.  It gives 6 ideas for other ways to grow onions and other kitchen gardening hacks.
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What are Spring onions?

With the common name, one would expect that this onion is one that grows in the spring. And you would be partly correct!

Spring onions are planted as seedlings in the late fall months and then harvested the next spring. They are sweeter and milder than regular onions, but the greens have a more intense in flavor than scallions.

You can also grow spring onions from seeds starting in early spring to have a less developed onion all summer long.

The spring onion plant is made of two parts, a white bottom part that has the roots, and the green top part which grows above the soil on a long stalk. 

Both parts can be used in recipes and have slightly different flavors.  It is very easy to grow spring onions.

There are many types of onions that home cooks use on a weekly basis. Spring onions are just one of them. Find out about the onion varieties here.

I use spring onions all the time when I cook.  They have a very mellow flavor that is perfect as a garnish and also makes a lovely sauce for most proteins.  So I like to have them on hand.

Several years ago, I was watching The Next Food Network Star show and one of their quick fire challenges was to give a quick kitchen tip.One of the contestants talked about re-growing spring onions in water so that you would never have to buy them again.

I had my doubts, but tried the project and found that it worked like a charm!  Not only that, it’s an easy project, fun for the kids to help out with and gives brings the outdoors inside as well.

What if you don’t have a garden where you can grow spring onions outside?  That doesn’t matter.  You can actually regrow store bought spring onions, as long as they have a some of the roots left on each plant.

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Here is how to regrow spring onions in water.

This trick will work for all types of these onions, whether they are spring onions, scallions or green onions.  The only difference will be whether you have a large or a slimmer bulb area in the water.

The main difference with re-growing spring onions is that you won’t get as many in a slim glass as those without the enlarged end, but all will sprout the green area easily with this process.

Sort out your onions or scallions, making sure that all of the onions have a least a few roots growing from the bottom. Take out any that don’t and save them for cooking later. The longer the roots are, the better for fast growth.Trim the tops of the onions and place them in a glass of clear water with the water just above the point where the onions start to turn green.

I find that the water stays fresh longer if I don’t have it all the way up where the green tips are.  

Any kind of see through jar will work. Mason jars are decorative, small clear vases work, or even a plain clear water glass.

You will want to be able to see what is happening as the spring onions regrow.

As you need spring onions for cooking, just cut off the green part of the onions above the water line and leave the base in the onion jar.

Change the water when it starts to get a bit funky. Every other day works for me.  

Keep the container near a sunny window if you can, so that the onions get some light.In a few days, the onions will start re-growing from the cut area.  You can re-cut again and again!  Free onions forever! (as long as you remember to change the water.)

My first shoots appeared in about 3 days.

Spring onions are just one type of what is called a cut and come again vegetable. Other vegetables that will regrow are Swiss Chard, lettuce and spinach.

My daughter knows how much I love to regrow spring onions in water. She gave me a small onion jar where I can keep my cut onions until they grow again.

This little vase is ideal for the spring onions that have a more pronounced white bulb area. They just sit side by side in it and I use the green parts for cooking Asian dishes. 

It is not unusual for me to have a couple of glasses of scallions or green onions growing and my little dish of spring onions.  I just love the flavor of them, so I keep them growing all the time!

It only takes a few days before you see the new growth and in about a week, you’ll have a bunch of new spring onion shoots.

These are the roots of the spring onions at just about 10 days.  They are so much longer than when I put them in the jar of water!

The beauty of this project is that you can do it over and over again.  Regrowing spring onions means that you’ll never have to buy them again!

Just be sure that you change the water every few days. If you don’t, the whole bottom area will get decayed and mushy. It is THAT easy to regrow spring onions!

Why won’t my spring onions regrow?

If you have trouble getting the spring onions to regrow, it could be one of these causes:

• The water is dirty. Be sure to change it every few days
• You have cut them too close to the root. Leave quite a bit of the white part for best results
• Not enough water.  If the onions water is too low, the onions will dry out and won’t grow.
• Too much water.  Don’t have the water level too high.  Cover just the bottom area and let the new growth occur above the water.
• Not enough sunlight. Move closer to a sunny window. Plants need some light to grow.

How many times can you regrow spring onions?

The answer to this question depends on how fastidious you are about replacing the water.  In theory, as long as the water keeps getting replaced every few days, the onions will keep growing out of the cut area.

My experience has been that I am forgetful and sometimes go longer than a few days before replacing the water.  The longer you allow the water to get murky, the less viable the onion bottoms will be.

Be careful not to add too much water to the green area. This makes the onions get soft and mushy and you will need to throw them away.

At the very least, though, you’ll get many cuts of the onions, even if you are a bit forgetful.

Pin these tips for how to regrow spring onions

Would you like a reminder of this post for tips on regrowing spring onions in water?  Just pin this image to one of your gardening boards on Pinterest so that you can easily find it later.

Admin note: This post first appeared on the blog in October of 2017. I have updated the post with new photos, more information on spring onions, a printable project card and a video for you to enjoy.

For more garden hacks, see my Garden Art and Recycling Board on Pinterest.

If you liked this project, why not try to grow onions indoors in a water bottle?

Yield: Never buy spring onions again!

How to Regrow Spring Onions in Water

Print

Spring onions are a great cut and come again vegetable. When you place the roots in water, they will grow and you can just keep reusing the green parts. See how to do this in this fun project that the kids will love.

Active Time 10 minutes

Total Time 10 minutes

Difficulty easy

Estimated Cost $3

Materials

• Clear glass or vase
• Bunch of spring onions
• Water

Tools

• scissors

Instructions

1. Sort the onions and take out those that don't have at least a few roots growing from the white end.
2. Trim the tops of the onions so they are all the same length.
3. Place them in a glass, or clear vase and add water to just above the white part of the onion.
4. Change the water every other day for new fresh water.
5. Place the glass near a sunny window.
6. In a few days, the roots will start growing.
7. You can cut off the green part of the spring onion to use in cooking.
8. New shoots will start to grow in about 3 days.
9. Cut again and again for recipes.
10. Now you have an endless supply of spring onions from just one batch.
11. Be sure to keep changing the water, or the onions will go mushy.

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