How to Cure Onions to Make Them Last for Months

Onions Are One of the Few Vegetables That Can Last for Months

onions in tray for storage
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Onions are one of the most essential ingredients for any cook. From soups to stews, they add flavor and enhance the dish, making it more delicious. 

Onions are one of the easiest vegetables to grow, and they also store very well. If stored properly in a cool and dark location, some onions can maintain their flavor and freshness for as long as one year. Learn how to cure your home-grown onions, and you won't need to buy any this winter.

What Onions Are Good for Storage?

There are two main types of onions, pungent and mild. Mild onions are large and juicy, frequently used on hamburgers and sandwiches. Mild onions do not last very long in storage. Under the most ideal conditions, they may survive for one to three months, but are inedible after that. However, they can be used to make salsa, pickles or can be caramelized, which can be frozen or canned to prolong their life. 

Pungent onions are very different. Smaller and less juicy than mild onions, they are usually the onions that induce tears when cut. The same compounds that cause tears to well up are the ones that preserve the onion, helping them last for months. 

Storing onions is very simple. By the middle of the summer, you can begin harvesting, but they'll continue to grow and flourish right into the early fall. 

How to Cure Onions

  1. Place the entire onion plant, including bulbs and leaves, in a cool dry place. You can hang the onions in bunches or spread them out on a rack to cure—whichever works best for you.
  2. Allow the onions to dry for two to three weeks or until the tops and necks feel dry to the touch, and the outer onion skin is shrunken and papery.
  3. Leave the leaves intact, if you plan to braid your onions. Trim them to within an inch of the bulb, if you plan to store your onions loose.
  4. Your onions are now ready for storage! Store them in a cool place; a temperature between 32 and 40 degrees is best. Make sure it has good air circulation; and they should stay fresh for months.

    Tips for Curing Onions

    1. Thick-necked onions do not store well. Neither do wet onion varieties, so be sure to use them first. If you have a lot of either variety, your best bet is to preserve them by freezing them.
    2. Don't store your onions near your potatoes. They'll cause each other to go bad faster. It's also best to keep your onions away from other fruits and vegetables that might absorb their flavor.
    3. Use some of your onions to make your own onion powder and onion salt.
    4. When you plan next year's garden, seek out onion varieties that are know to store well. These will often be referred to as keeping onions or storage onions in the garden catalogs. Typically dry, pungent onions store best. They're the ones that really make your eyes tear and sting when you cut them. It's the sulfur in the onions that causes this effect, and it's that same sulfur that protects them from rotting.