When Are White Onions Ready To Harvest

Knowing when are white onions ready to harvest is the key to getting bulbs that store well and taste great. Picking them at the perfect time makes all the difference.

If you pull them too early, the bulbs will be small and the skins thin. Harvest too late, and you risk rot or the onions bolting (sending up a flower stalk). This guide will walk you through the clear signs to look for, so you can harvest with confidence.

White onions are ready when the plants themselves tell you they’re done. Unlike some vegetables, you don’t judge mainly by size or color of the bulb underground. Instead, you watch for signals from the tops.

The most reliable sign is when the green onion tops (the leaves) begin to fall over and turn yellow or brown. This natural process is called “lodging.” It means the plant has stopped growing and is starting to dry down, focusing its final energy into bulbing up and forming that protective papery skin.

The Top Signs Your Onions Are Finished Growing

Tops Falling Over: About half to three-quarters of the tops will flop over at the neck. They won’t stand up straight anymore.
Leaf Color Change: The green leaves fade to yellow, then brown, starting at the tips and moving down.
Neck Softening: The neck of the onion (where the leaves meet the bulb) becomes soft and bends easily.
Papery Skin: The outer layer of the bulb develops a dry, paper-like texture. You might see it peeking above the soil.

Typically, white onions reach this stage 100 to 120 days after planting, depending on the variety. Always check your seed packet for the specific “days to maturity.”

What to Do If Your Onions Flower (Bolting)

Sometimes an onion sends up a central flower stalk. This is called bolting. It’s often triggered by a sudden cold snap after warm weather.

Once an onion bolts, it stops putting energy into the bulb. The bulb won’t grow larger and it won’t store well. When you see a flower stalk, you should harvest that onion right away for immediate use in your kitchen. Don’t try to store it with your other onions.

The Step-by-Step Harvest Process

Harvesting isn’t just a quick pull. Proper technique ensures your onions last for months.

Step 1: Choose the Right Day

Pick a dry, sunny day. Harvesting after a rain or when the soil is wet can introduce excess moisture and lead to mold during storage. The ideal is a stretch of sunny weather.

Step 2: Loosen the Soil

Don’t just yank the tops. Gently insert a garden fork or trowel several inches away from the bulb to loosen the soil. Then, carefully lift the bulb out. This prevents damage to the base or neck, which is a major entry point for rot.

Step 3: Handle with Care

Bruises and cuts will shorten storage life. Handle your onions gently, like eggs. Avoid dropping them into a hard basket. A soft garden crate or bucket is better.

Curing: The Most Important Step for Storage

Curing is the process of drying down your onions to seal the neck and outer skin. Skipping this step is the number one reason homegrown onions spoil quickly.

Lay Them Out: Place your harvested onions in a single layer. Don’t pile them on top of each other. They need good air circulation on all sides.
Find the Right Spot: A warm, dry, well-ventilated area is perfect. This could be a covered porch, a garage with fans, or a shed. Avoid direct hot sunlight, which can actually cook the bulbs.
Let Them Dry: Leave the onions to cure for about two to three weeks. You can leave the tops on; they help with air circulation. The curing is complete when the outer skins are completely papery and rustle to the touch, the neck is totally dry and tight, and the roots are shriveled.

How to Tell When Curing is Complete

The neck is completely dry and closed tight.
The outer skin is crisp and papery all over.
The roots are dry and brittle.
You can easily hear the skins rustle when you handle them.

Preparing Your Onions for Long-Term Storage

After curing, you need to prep your onions for their winter home.

Trim the Roots: Use clean scissors or pruners to cut off the dried roots, leaving about a half-inch.
Trim the Tops: Cut the dried foliage down to about one inch above the bulb. If you plan to braid your onions, you can leave the tops long.
Final Inspection: Gently feel each onion. Any that have soft spots, thick necks that didn’t close, or signs of bruising should be set aside for immediate use. Only store perfect, firm, fully-cured bulbs.

Best Practices for Storing Your Harvest

White onions, when cured properly, can store for several month. The goal is to keep them cool, dry, and dark.

Temperature: Aim for 35-40°F (2-4°C). A cool basement, cellar, or unheated garage is ideal. Avoid places that freeze.
Humidity: Keep humidity low, around 65-70%. Too much moisture causes mold and sprouting.
Airflow: Store them in mesh bags, old nylon stockings, or woven baskets. Never use sealed plastic bags, which trap moisture.
Check Regularly: Every few weeks, give your stored onions a quick look. Remove any that are starting to soften or sprout immediately to prevent spoilage from spreading.

Common Harvesting Mistakes to Avoid

Harvesting by the calendar alone. Always use the visual signs (tops down, yellowing) as your primary guide.
Pulling onions instead of lifting them. This can break the stem off the bulb, ruining it for storage.
Skipping the curing process. This step is non-negotiable for storage onions.
Washing the bulbs before storage. Brushing off dry soil is fine, but never introduce water.
Storing damaged onions. One bad onion can spoil the whole bunch.

FAQ: Your White Onion Harvest Questions

Can I harvest white onions early for green onions?

Absolutely! You can thin your onion patch by pulling young plants to use as scallions or spring onions at any time. This gives the remaining bulbs more space to grow.

How long after tops fall over should I harvest?

Once most tops have fallen, you should harvest within 1-2 weeks. Don’t leave them in wet soil for too long after this point, as the bulbs can start to rot.

What if it’s going to rain at harvest time?

If the tops are down and rain is forecasted, it’s better to harvest and get them under cover than to leave them sitting in soggy soil. Just be extra diligent about curing them in a well-ventilated spot.

Why are my onion tops not falling over?

Sometimes, especially in very fertile soil, onions keep producing green tops. If it’s past your variety’s maturity date and the necks are still stiff, you can gently bend the tops over yourself to encourage the plant to start shutting down.

Can I eat onions right after harvest?

Yes, you can eat them immediately. They are often more juicy and pungent before curing. Fresh, uncured onions are fantastic for cooking but won’t last long on the counter.

Timing your white onion harvest perfectly is a simple matter of observation. By watching for those tops to fall and taking care during lifting and curing, you’ll be rewarded with a bountiful supply of homegrown onions that will keep your kitchen stocked long after the growing season ends. There’s nothing quite like the satisfaction of reaching into your own storage in January for an onion you grew yourself.