It’s common for onions to start sprouting in our kitchens. Discover why you might want to skip eating a sprouted onion and consider growing it instead.
You can also grow your own ginger plant using a root from the grocery store.
About Sprouted Onions
It’s very common for onions kept in typical household conditions to start growing green sprouts or tops. These are the bulbing onions with the papery skins, used either raw or cooked.
For optimal storage, onions should be kept in cool, dark, and fairly dry conditions, ideally between 55 to 65°F (13 to 18°C) with moderate humidity.
But, even in the darkness of a kitchen cabinet or pantry, conditions are likely to be too warm or humid. Our kitchens are commonly around 70°F (21°C) and warmer when cooking —not good for storing onions long-term but perfect for causing sprouts to grow.
So, are sprouted onions safe to eat? Or, could I also regrow them?
The short answers are yes and yes.
Yes, sprouted onions are safe to eat. But you might not like the taste. Keep reading for the explanation.
And yes, you can regrow them. I’ve included complete instructions below.
Contents
How to Regrow Sprouted Onions
The image (above) shows a sprouting cooking onion.
To regrow it, remove the sprouts, including the roots, and set aside the rest for cooking if it’s still fresh.
Without the roots, they cannot regrow.
Sprouted onions can be grown in the ground or containers, indoors or outdoors.
If growing in containers, use a potting mix made for organic vegetable growing.
Each onion may have several green shoots that can be separated into multiple plants.
As the sprouted section grows, a new onion bulb will form at the base.
I’ve included planting instructions below.
Random Cool Fact
The edible parts of bulbing onions—those layers that we can peel away—are actually modified leaves, also known as bulb scales.
Frequently Asked Questions
Yes, sprouted onions are considered safe to eat but they likely will not taste very good.
Yes, sprouted onions taste different than non-sprouted ones. When bulbing onions start sprouting, the new growth gets some of its energy from the sugars within the bulb. This means the edible parts have been depleted of some of that natural sweetness we know and love, and the texture is a bit tougher.
Some people like the slightly duller flavor, others do not.
For me, it depends how far along the green growth is. If there’s just a little sprout sticking out, it means the onion will pretty much still taste fine because it hasn’t surrendered that much of its sugars yet.
If the sprouts are a few inches long or more, the main onion part is going to be super bland.
This article at Cook’s Illustrated describes their taste test: Using Sprouted Onions.
Yes, onion sprouts or shoots are edible but the taste may be unpleasant.
The best way to salvage the onion is to cut it open, pull out the entire green shoot and roots, and use the rest.
The green sprout grows from the root of the onion, up through the middle and out the top, so it should be simple to remove.
If you want to regrow the green shoot, see the instructions below before cutting.
Regular and sprouted onions may cause issues for animals. Cats, dogs, and some other animals do not do well with onions—sprouted or not—and can get ill from them. If you have a pet that randomly nibbles, keep the onions and onion plants away.
Yes, you can regrow sprouted onions. In fact, because they are already sprouting (growing), you’ve confirmed they can regrow and they have kindly given you a head start.
Some grocery store foods are treated with growth retardants to stop this from happening, but, if yours is sprouting, it’s good to grow.
Growth depends on the root base remaining intact. You may even notice little hairy roots there. That’s what contains the ability to regrow.
You can grow/regrow your sprouted onion as a houseplant in a sunny location or plant it in your garden (either in containers or the ground). Often there are several plants sprouting within each onion. These may also produce flowers.
Just like sprouted onions, sprouted garlic is safe for humans but the taste is altered. If the sprouts have just started, cut them out and use the rest of the bulb for cooking. You can also plant and grow them.
You can prevent garlic and onions from sprouting by providing suitable storage conditions. It’s light and warmth that cause sprouting.
Store both in a cool, dark, dry place with temperatures between 55 to 65°F (13 to 18°C). This is often a lower temperature than we have in our kitchens.
Moderate humidity will help prevent drying out.
It is not recommended to store onions in a fridge.
Yes, you can regrow shallots if the bulb and roots are still intact. If you just have the green edible parts without the roots, no, they cannot regrow.
Resources
Ebook
Kitchen Propagation Handbook
7 Fruits & Vegetables To Regrow As Houseplants
by Melissa J. Will
Learn how to grow houseplants from avocado, oranges, lemons, ginger, and more using leftover pits, seeds, and roots.
About This Ebook | Visit Ebook Shop
This ebook is a digital file (PDF format) you save to your device. It is not a physical product.
PayPal, Credit Card, Apple Pay
Available in 
United States & 
Canada only
Listen
So, there you go. Another one of life’s great mysteries demystified.
Let me know if you grow your onions and how it turns out. It can be quite different growing them indoors versus outdoors. I find indoors is always much slower but they do make interesting decorative houseplants. And, bonus if it ends up flowering.
If you like this stuff, sign up for the free Empress of Dirt newsletter and you’ll get fresh garden ideas delivered right to your inbox.
~Melissa the Empress of Dirt ♛
How to Plant a Sprouted Onion
Equipment
Supplies & Materials
- 1 Onion, sprouted
Instructions
- Carefully cut open onion, avoiding cutting middle section, and remove green sprout/shoots without damaging them. You may have several individual shoots to plant.
- With root ends down (green shoots up), plant approximately one-inch deep, keeping bulb submerged and green shoots above soil level.
- If planting more than one, space at least 2-inches apart.
- Water until potting mix is moist.
- Grow in sunny location never allowing soil to dry out.
