Onions are vegetables that hold up well for at least a few days.
However, they eventually spoil or sprout, depending on the environment you store them in.
Let’s take a look at the common onion varieties that sprout when left in storage for a long time.
9 Onions that Sprout
Onions are underground stems that remain dormant until the conditions are favorable for sprouting.
When they’re stored for too long, these vegetables will eventually produce roots and shoots.
So, when a green sprout emerges from an onion, it means the vegetable is trying to regrow.
Left to themselves, the shoots and roots will grow long, and you can use the onion to grow more onions.
Let’s take a closer look at the common onions that sprout when kept in storage.
1. Bermuda Onions
Bermuda onions are sweet onions with pale yellow skin. They have a flat shape. These onions are moist and juicy.
They have higher sugar content than most other onions.
They’re also low in sulfur and hence not very pungent.
These onions have delicious mild flavors. Hence, they don’t store well for too long.
Bermuda onions produce sprouts in the presence of moisture and sunlight.
Onion bulbs will produce roots and shoots that turn into long green stalks.
You can use the onion if you cut off the stalks as soon as they appear.
However, the onion won’t be usable if the stalks grow too long.
You can either plant these sprouted onions or discard them.
2. Walla Walla Onions
Walla Walla onions are sweet onions that exclusively grow in the Walla Walla Valley of Washington.
They’re medium or large and have crunchy white flesh.
These onions are highly prized for their unique sweet flavor.
You can eat them raw because they lack the characteristic pungency of other onions.
Walla Walla onions grow well from transplants.
Since it’s a sweet variety, it doesn’t hold up well in storage for too long.
Leaving it in the pantry or refrigerator for too long will encourage fresh growth, and the onions will produce sprouts.
You can transplant sprouted Walla Walla onions and grow more onions from the sprouted ones.
3. Welsh Onions
Welsh onions are a type of spring onions that grow vigorously.
They grow as clumping plants with thick stems and exquisite flowers that make them look beautiful.
The sprouts grow thickly and profusely under favorable conditions.
You can find these onions in grocery stores, where they’re sold in bunches.
The leaves are snipped off the plants and used to season or garnish soups, salads, and other dishes.
Welsh onions come with tiny roots. When left in storage for too long, these roots grow bigger and become visible.
The stalks will even produce chunky flowers when left to grow.
However, you can use Welsh onions even after they sprout.
All parts of the plant, including the shoots, flowers, and bulbs, can be consumed.
4. White Onions
White onions aren’t as widely available as other varieties like yellow and red onions.
Nevertheless, they’re the perfect onions for certain recipes and cuisines.
For instance, these onions find wide use in Mexican cuisine. They’re used both in the raw and cooked form.
They form a great addition to salsas, salads, taco fillings, chutneys, and stews.
White onions hold up for a long time in storage. They have high sulfur content and hence don’t spoil easily.
However, they will sprout if you keep them for too long in a humid environment.
A green shoot will emerge from the top of the onion, which means that the onion is trying to regrow.
The shoot will be dark green and thick. The onion will also produce roots once it starts sprouting.
You can plant the sprouted onion, and it will give rise to more onions.
However, if the sprout has just emerged and isn’t too big, you can chop off the center and use the rest for cooking.
5. White Grano Onions
White Grano onions are sweet onions with stark white skin and flesh.
They were first developed as an experimental onion in Valencia, Spain.
These onions are mildly pungent because they have low sulfur levels.
However, they’re very sweet and can be eaten raw or added to salads and salsas for their delicious flavors.
White Grano onions are suitable only for short storage because they start sprouting when stored for too long.
When they sprout, they produce thick green leaves and long roots.
6. Candy Onions
Candy onions are large hybrid onions with a flattened shape. They have light and papery brown skin.
The flesh is juicy, white, and firm. These onions are crispy and sweet.
They’re not pungent and can be eaten raw. They are also good for cooking.
Candy onions will hold up in storage only if they have been properly cured.
If not, these onions will quickly sprout or rot.
Candy onions develop long and narrow stalks when kept for too long. They will also have visible roots.
A single Candy onion will grow several sprouts.
You can separate them and transplant them to produce several new onion plants.
7. Vidalia Onions
Vidalia onions are one of the sweetest onion varieties.
They’re a type of Yellow Granex onions.
They’re exclusively trademarked for select areas of Georgia where the sulfur content of the soil is very low.
For this reason, Vidalia onions are sweet and hardly pungent.
These onions don’t hold up for too long. They tend to sprout or spoil faster than other pungent types of onions.
Sprouted Vidalia onions can be planted to produce more onions.
However, the soil condition is critical in determining the yield that will be produced.
Unless the soil has low sulfur levels, the onions won’t turn out to be sweet.
Shallots are a member of the allium family, like onions.
They have similar flavors and resemble onions but are smaller.
Shallots have red papery skin and dark purple flesh.
They have an elongated, oblong shape.
They’re widely used for pickling. They’re also good for cooking.
Shallots are pungent, with sharp and acidic flavors. They also have sweet notes seeping through.
Shallots hold up for a long time when you store them in a dark and dry location.
However, they will sprout when the conditions are favorable.
These onions will even develop shoots and roots if you keep them in the refrigerator for too long.
Sprouted shallots will have light green shoots and tiny white roots.
The shoots will grow long when you leave them untouched.
9. Texas Super Sweet Onions
Texas Super Sweet onions are Yellow Granex onions with a short shelf-life.
These onions have a flattened shape, with papery brown or yellow skin.
Beneath the papery skin, they have white flesh. They’re very sweet and flavorful.
You can eat them raw or use them for cooking.
These onions don’t take too long to sprout when kept in storage.
Heat and moisture accelerate the sprouting process.
Sprouted onions have light green shoots and long white roots.
The leaves grow thicker as the sprouts age, and you can use these sprouted onions to grow new onions.