How To Know Onions Are Ready To Harvest

Knowing when to pull your onions from the ground is the key to a harvest that stores well for months. This guide will show you how to know onions are ready to harvest for that perfect golden, firm result.

It’s not just about the calendar date. Onions give you clear physical signals. If you harvest too early, the bulbs will be small and won’t store. Harvest too late, and they might rot or bolt. Getting the timing right means you’ll enjoy your own onions long into winter.

This is the main event. Your onions are ready when the plant itself tells you it’s finished growing. Look for these two unmistakable signs in your garden.

First, the tops will begin to yellow and fall over. This isn’t a sign of disease; it’s the plant’s natural process. The leaves are sending their final energy down into the bulb. About 20-25% of your tops should be down before you take action.

Second, the neck of the onion—the area where the leaves meet the bulb—will start to feel soft and weak. It will lose its rigidity. This is a critical indicator that the onion has stopped growing and is beginning to cure even while still in the soil.

The Visual Cues: What to Look For

Your eyes are your best tool. A ready onion has a specific look.

Foliage Color: Green tops turn a yellowish-brown. They lose their vibrant green color.
Top Condition: The leaves flop over naturally. They don’t stand upright anymore.
Bulb Appearance: The outer skin of the bulb, just at the soil surface, may start to look papery or shiny.

The Touch Test: Feeling for Firmness

Looks can be deceiving, so always use your hands. Gently brush away a little soil from the shoulder of a few bulbs.

Press gently on the neck. It should feel softer and less juicy than a growing onion.
The bulb itself should feel solid and firm all the way around, not squishy.
The outer skin should be dry and tight, not loose or slimy.

Timing and Weather Considerations

Onions are photoperiodic, meaning they bulb in response to daylight hours. But weather plays a huge role.

Stop watering once tops begin to fall over. This encourages curing and prevents rot.
If heavy rain is forecast and your tops are mostly down, consider pulling them to avoid them sitting in wet soil.
Don’t wait for 100% of tops to fall. Once the majority are down, it’s time.

The Harvest Process: Step-by-Step

Harvesting correctly protects your onions and prepares them for curing.

Choose a Dry Day: Always harvest when the soil is dry and the sun is out. Wet onions are prone to mold.
Loosen the Soil: Use a garden fork to gently loosen the soil around the bulbs. Avoid stabbing the bulbs themselves.
Lift, Don’t Pull: Carefully lift the onions out of the ground. Yanking can damage the neck or bruise the bulb.
Handle with Care: Place them gently in a crate or basket. Bruises will lead to spoilage during storage.

What About Green Onions?

Green onions, or scallions, are a different story. You can harvest these any time they reach a usable size. They are meant to be eaten fresh and do not need the curing process.

The Crucial Curing Stage

Curing is not optional; it’s what makes onions storage-worthy. This process dries the outer layers and neck to seal the bulb.

Find the Right Spot: Lay onions in a single layer in a warm, dry, well-ventilated place. A covered porch, garage, or shed is perfect.
Arrange Properly: Spread them out so air can circulate around each bulb. You can lay them on a screen or hang them in bunches.
Let Them Be: Leave them to cure for 2-4 weeks. The outer skins will become papery and rustle to the touch.
Check the Necks: The most important sign is a completely dry, shrunken neck. It should feel tight and wiry.

How to Store Your Onions Long-Term

After curing, you need to prep them for storage. This final step ensures months of use.

Trim: Cut the dried tops down to about 1-2 inches above the bulb. You can also trim the roots.
Inspect: Feel each onion again. Any that are soft, have thick necks, or show damage should be used first. Only store perfect, firm bulbs.
Choose a Container: Use mesh bags, old pantyhose, or a well-ventilated crate. Never use plastic bags.
Find the Right Environment: Store in a cool, dark, dry place with good air circulation. Ideal temperature is between 35-50°F (2-10°C).

Common Problems and Solutions

Sometimes things don’t go perfectly. Here’s how to handle common issues.

Bolting (Flowering): If an onion sends up a flower stalk, harvest it immediately. The bulb won’t grow larger and won’t store well. Use it soon.
Thick, Green Necks: Onions with necks that don’t soften may have gotten to much nitrogen late in the season. They are more prone to rot; use them quickly.
Soft Spots: Any onion with a soft spot should be discarded or used immediately. It will not store and can spoil others.

FAQ: Your Onion Harvest Questions Answered

How long do onions take to grow before harvest?

Onions typically need 90-120 days from planting sets or transplants. Always check the days to maturity for your specific variety, as it can vary.

Can you leave onions in the ground too long?

Yes, you can. If left in wet ground after maturity, they can start to rot or develop secondary root growth, which ruins them for storage. Its important to get them up at the right time.

What if my onion tops haven’t fallen over?

If it’s late in the season and growth has stopped, you can gently bend the tops over yourself. This signals to the plant to start the bulbing and curing process. Avoid breaking them.

How do you harvest onions so they grow back?

Onions are a once-and-done crop. They will not regrow from the bulb once harvested. For a continuous supply, plant successions of green onions throughout the season.

Why are my harvested onions not getting dry?

High humidity or lack of air flow are the usual culprits. Ensure they are in a breezy spot. A fan can help in a humid climate. They just need more time if the weather’s been damp.

Mastering the harvest is the most satisfying part of growing onions. By watching for those golden, falling tops and feeling for firm bulbs, you’ll pull them at the perfect moment. With proper curing and storage, your homegrown onions will be a kitchen staple for many months, a true reward for your gardening effort.