When To Harvest Red Onions – Gardening Tips 2024

Save for later!

From its vibrant purplish-red color to its crispy texture and mildly sweet and spicy flavor, you will never run out of uses for red onions.

Even better, growing this vegetable in your backyard garden is as easy as any other type of onion crop.

The key is knowing when is the best time to harvest them.

When to harvest red onions? If you want full-sized red onions, you will have to wait three to four months after planting. Depending on when you start onions, harvest time could be anywhere from late August to early October.

How Do You Know When Your Red Onions Are Ready to Harvest? 

While they take their sweet time to mature, it’s easy to tell when red onions are ready to harvest.

More than anything, you’ll want to watch out for large, full-sized bulbs and yellowing tops.

Given the right growing conditions, the mature bulbs should grow to approximately two to three and three-fourths inches in diameter.

Besides reaching its full size, another indicator of maturity is the onion’s neck.

When the neck is still stiff, that means your red onion bulbs need more time to mature.

In comparison, onions ready for picking will have necks that are a little lighter in color and bend flat.

Do not harvest if the necks are still going straight out; instead, wait for them to bend.

What Happens if You Don’t Harvest Red Onions? 

Once you notice that the tops have bent over and are down on the ground, leave the bulbs as is to fully mature.

They can stay on the ground 10 to 14 days like that, but we don’t recommend waiting too long.

If you don’t harvest red onions within that timeframe after their tops have died, you’re leaving them open to harmful organisms.

There’s a good chance they will rot earlier than usual, or they may even start growing again.

How To Grow Red Onions

For red onions to flourish and be ready to harvest three to four months after planting, you must ensure that you give them their preferred growing conditions.

Not only should the soil be well-drained and fertile with compost dug in, but the plants should also receive full sun.

When spacing your onion plants, give each one six inches of growing space.

Also, red onions have shallow roots, so a regular watering schedule is an absolute must.

That said, you’ll also want to be careful of overwatering, as too much water can cause the bulbs to rot or for fungi to form.

The rule of thumb is ensuring they get about an inch deep of water each week.

Alternatively, remember only to water when the top three to six inches of soil is dry.

How To Harvest Red Onions

By following these growing tips, your red onion crops should be ready for harvest in about 100 to 175 days.

When it comes to harvesting, the most important rule to follow is to dig up the bulbs before the cold hits.

It would be best to harvest your mature red onions before the first frost, as they may spoil in the cool fall temperature.

Since you will most likely plant your onions in spring, they should be ready to harvest come summertime.

Here’s what to do when harvest time arrives:

Step 1: Regularly check if your onions are blooming.

When onion plants bloom, it means that all the plant’s energy is focused on the flowers.

This indicates that the onion bulbs have already stopped growing. It is time to pull them out of the ground immediately.

Onions that have their plants form flower stalks do not need to be cured.

Unfortunately, they also do not store well, so you need to consume them within three days.

Step 2: Wait for the tops to fall over.

If your onion plants do not form flowers, you can wait for the green foliage to fall over to signal harvest time.

Then, when the green leaves turn yellow, it means that you can harvest them.

Step 3: Use a spade to loosen the soil around the bulb.

When pulling out onions, start by carefully digging a circle around the bulbs beforehand.

Next, cut the roots using your spade, but be extra careful when doing so. If you happen to cut the onion itself, it will rot prematurely.

Step 4: Pull up the plant from its neck.

To uproot the onion, firmly hold the neck, which is at the base of the green leaves that have bent over.

There shouldn’t be much resistance as you pull it out from the ground.

If you’re having a hard time uprooting the bulb, loosen the soil around it more using your spade.

Carefully handle the onions so that you do not bruise them or you risk premature rotting.

How To Cure Red Onions

After harvesting, the next step is to cure your red onions. Here’s how to do that:

Step 1: Leave them on the ground.

If the weather allows, let your onions sit on the ground for two days. The goal is to allow the outer skin and the roots to dry out.

Only bring the onions inside if it starts to rain. The moisture alone from the rain is harmful to the onions, causing them to rot.

If you can’t help it and it’s the rainy season, place your onions inside a cool dry shed to keep them from spoiling.

Step 2: Cut the tops.

Use scissors or grafting shears to cut off the green tops.

Make sure to leave at least one inch of green foliage to keep the onion from rotting.

Step 3: Cut the roots.

Again, you will want to use scissors or grafting shears to cut off the roots.

Cut the roots as close to the onion as you can but be careful not to damage the bulb.

Step 4: Store the onions.

For two weeks, store the onions in a shady and well-ventilated space.

Spread them on the ground and keep them out of direct sunlight to allow them to dry out more.

Step 5: Put the cured onions in a nylon stocking or a mesh bag.

Placing your red onions in a nylon stocking or a mesh bag will stop them from forming mold.

It will also protect them from bruising, which is a very serious risk for onions.

Should You Wash Red Onions After Harvesting? 

As discussed in the curing process, you must keep the onions dry with good ventilation to prevent them from rotting.

We don’t advise washing the onions after harvesting. Even moisture from the rain may already cause rot to the onions.

What you can do is brush off the dirt instead. In fact, even before cooking, it is not necessary to wash onions.

While most fresh produce requires at least a quick rinse, onions get a pass on this step.

The reason? Onions are one of the cleanest vegetables when it comes to pesticide exposure.

However, if you’re planning to eat them raw, it does not hurt to wash them in cool water to be safe.

Can You Eat Red Onions Immediately After Harvesting? 

Yes, you can eat raw onions right after harvesting. Wash them with water and go on and take a bite.

While it is possible to eat them raw, red onions are best enjoyed when put in other dishes.

1. Add them on a grilled platter

Grilling red onions brings out their natural sweetness.

As such, they are best paired with tomatoes, unripe mangoes, fish, and meat.

2. Put them in salads.

As you probably already know, the mild sweetness of red onions never disappoints.

Be it an orange and onion salad or a cucumber, tomato, and red onion salad, the addition of red onion will surely level up the flavor of your dish.

3. Create a homemade pico de gallo.

Who doesn’t love pico de gallo?

With just tomatoes, red onions, some garlic powder, and jalapeno pepper, you can make your own pico de gallo.

It is so delicious and effortless to make that you will never go back to eating store-bought pico de gallo again.

4. Pickle your onions.

Pickling your onions is yet another good use for your fresh harvest.

It will just take you five minutes to make, and you probably already have all the ingredients in your kitchen.

All you will need is vinegar, salt, sugar, and warm water, and you are all set.

You will love having this in your fridge for when you have avocado toast, tacos, and more.

Are Red Onions Worth Growing?

With their deep reddish-violet color and slightly sweet flavor, you will never get enough red onions.

What’s more, eating them might just be the best thing you can do for your health.

Not only does it help control diabetes and lower high cholesterol, but it also helps ease arthritis symptoms and other similar conditions.

Some even believe that it can assist in addressing digestive issues and sore throats.

For these benefits (and the fact that they are easy to grow), there’s no reason why you shouldn’t grow red onions.

Related Articles:

Save for later!

Leave a Comment