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- Knowing when and how to harvest onions helps you get the best flavor and longer storage life.
- Onions are ready to harvest when their green tops turn yellow and naturally fall over at the neck.
- Let onions dry for two to three weeks in a cool, shady spot before storing them to avoid mold and spoilage.
It's easy to tell when some vegetables are ready to harvest, but others are a bit more complicated. Carrots and sweet potatoes, for example, grow underground—as do bulb varieties like garlic—so it's often hard to know when to harvest them. Onions also fall into this category.
Here, we spoke to gardening experts about how to properly harvest onions. Follow this guide for fresh, delicious vegetables with the best possible flavor.
- Meg Austin, gardening instructor and fifth-generation farmer
- Teri Speight, landscape gardener, gardening coach, podcast host, and co-author of The Urban Garden
When to Harvest
Refresh your memory on the number of days until maturity for the specific onion you planted. This statistic can vary widely depending on whether you're growing short-day, long-day, or day-neutral varieties—or if you're planting from seed, sets, or transplants.
Then, watch for other signs. "When onions are ready for harvesting, approximately half the foliage will fall or bend," says gardening coach Teri Speight. "It's signaling the energy to focus on the onion below ground."
How to Harvest
Harvesting these vegetables isn't difficult. However, there are a few basic steps you should follow for maximum flavor and freshness.
1. Recognize the signs. "You’ll know your onions are ready to harvest when the green tops start to yellow and the neck softens and naturally flops over," says gardening instructor Meg Austin.
2. Prep the soil. It's helpful if you spend a bit of time preparing the onion bed for harvesting. "Choose a dry day to harvest, and gently loosen the soil to avoid bruising the bulbs," says Austin. A small garden fork can help.
3. Harvest the onions. Use the green stalk of each onion as a handle. "Gently pull the onions and brush off any excess dirt," says Austin. "Don’t wash them—moisture will grow mold."
4. Dry your crop. The most time-consuming part of the harvest is drying the onions so that they can be properly stored long-term. "Lay the onions out in a single layer in a shady spot with good air flow to cure for about two to three weeks," says Austin. "When the necks are fully dry and the outer skins are papery, trim the tops and roots and store them in a cool, dry place."
How to Cure
If you plan to eat your freshly harvested onions immediately, then you don't need to cure them first. If you plan to store your onions for a longer period, you'll need to cure them by letting them dry for up to three weeks.
"Allow them to fully dry," says Speight. "Make certain the storage area is cool, dry, and dark. This will make certain the flavor is maintained and the bulb quality is kept intact."
Even if the onions look dry after a few days, give them the full two to three weeks to cure," says Austin. "This process is what seals the outer layers and dries the necks, which is key for long-term storage. If you trim or store them too soon, they’re way more likely to mold or rot."
