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How to Store Onions Long Term: The 6 Best Methods

Onions are a staple vegetable in the home. They are a base ingredient for many different kinds of soups, sauces, and meals. How to store onions long term is a vital skill for anyone managing food storage.

How to Store Onions Long Term

You can store onions long term in many ways, but if you want to store them whole or you want that crunchy texture, then you have to know which method is best for that.

We explore several methods for storing onions long term in the following sections.

How to Store Onions So They Last

The typical way to store onions long term is in a dark, cool area. In the past, people would have used a root cellar for this. In modern times we often keep them in a dark cabinet or pantry. Both of these methods work pretty well to extend the shelf life of onions.

Did you know that storing onions long term with potatoes will shorten the shelf life of the potatoes? So keep them separate!

The best way to make them last through simple storage is to hang the onions in a cool dark place. This way, they are not stacked on top of one another.

How Long Do Whole Onions Last?

There are a few ways to store whole onions. You can freeze them for years, but they will not retain the same fresh texture that onions typically have.

There are better methods for storing whole onions. If you want to know how to store onions long term for fresh use, then check out the curing option below.

Harvest at the Right Time

Harvesting onions at their peak gives you a healthy onion. This is how to store onions long term.

Harvesting Onions

The best time to harvest onions is around midsummer. The bulbs will begin to flatten, and the leaves of the onion will begin to flop over.

Methods for Storing Onions Long Term

If you want to put onions away for even longer than typical storage methods, then there are things you can do. We have a number of different ways if you want to learn how to store onions long term.

1. Pickling Onions

A good pickle is going to extend the shelf life of your onions by as much as a year. I like to slice red onions thin and create a sweet brine to pickle them. I mix them with thinly sliced jalapenos. It sounds like it might be a little much, but the sweet pickle counters the heat.

Pickled Onions

Sweet Brine

  • 2 cups of vinegar
  • 2 cups of sugar
  • 1/4 cup of salt

Bring the mixture to a boil and cool.

You can put a great condiment on the shelves for the long term with this practice.

2. Fermenting Onions

Fermented onions may not be something you are accustomed to, but they are a very tasty way to store onions long term. Fermenting also imparts loads of beneficial bacteria.

The process is simple.

Add 4 large onions, sliced, to a mason jar or larger container and pack them down. Then add 6 cups of water and 2 tbsp of salt to the jar. Cover it and sit it on the counter. After 24 hours, loosen the lid and let the CO2 escape.

After a week, you can place the lids on them and store them in the fridge.

The pH of your brine ferment should be below 4.0, and this keeps harmful bacteria from growing. You can usually tell the pH is off because of a strong rotten egg smell.

Just start over if this is the case.

3. Canning Onions

Canning onions is another process that will remove the crunch but will preserve the onion and its flavor for years. Onions are not acidic vegetables, so they will need to be pressure canned.

Canning Onions

You need a simple, straightforward recipe for this.

4. Drying Onions

Drying onions is dominated by two popular methods. Dehydrating and freeze-drying. Both work great and can create a dried onion that will last for years when stored in a way that protects them from moisture.

Freeze drying is expensive and consumes a lot of energy. Dehydration can be achieved in a slow, low oven, in a dehydrator, or even in the sun by slicing the onions thin.

5. Powdering Onions

In the restaurant world, onions are powdered using the help of a microwave and a herb grinder. By microwaving thinly sliced onions until they are completely dry, you can then grind them down to powder.

However, drying them in an oven or dehydrator will work, too. A good food processor can help, too.

6. Curing Onions

When we talk about curing onions, we are not talking about salting them. We are talking about placing the onions in a cool, dry place until the leaves wither up and dry. The outer layer of the onion will also get papery and dry.

At this point, your onions have cured. This is another method for storing onions long term.

How to Store Cured Onions

At this point, you are looking for a dark storage area with a temperature of 55 degrees or down to 38 degrees to store these onions. Here they can last for as much as 6 -8 months!

A root cellar is a perfect place for ured onion storage.

Can You Freeze Onions?

Onions freeze best after you have sauteed them or cooked them in some way. The freezing process breaks down the cellular structure of the onion, which makes them crunch, so when it thaws, it goes soft.

Sautee the onions a bit and season them. If you can lay them out in a thin layer and freeze them, that is best. Then break up the frozen sauteed onions and place them in freezer bags.

Wrapping Up How to Store Onions Long Term

As you can see, if you know how to store onions long term, you can fill your pantry, cellar, cabinets, and even spice rack with them. Onions are versatile when it comes to food preparation, but they are also versatile when it comes to preservation.

Choose the right variety of onions to grow, and when it comes time to cure or dry them, you will have great success. You might also consider a root cellar as it is the perfect place to store these onions but also other fruits and vegetables. Root vegetables like carrots and turnips are also great for long term storage.

For more information about storing survival food, check out our Food Preservation section.