Can Onions Survive Frost?

Onions are a staple of the vegetable garden, but when winter comes near, you may be wondering if this root vegetable can survive frost.

Onions can survive a brief period of frost, but prolonged exposure to cold can damage the plant. The onion plant will survive short-term (30-minute) freezes as long as the ground is not frozen. In USDA Hardiness Zones 5 through 8, this means that you can leave your plants in the garden during winter, or harvest them and store them in a cool place.

In cold climates, onion plants are susceptible to winter kill. When the temperature drops below 25 degrees Fahrenheit, your onions may die back completely and not come back next season. If this happens, don’t worry — you can grow new onions from sets or seeds next year!

How Tolerant Are Onions To Cold Weather

Onions are hardy plants that can survive cold weather and freezing temperatures if they’re properly protected. You can grow onions in almost any climate as long as they aren’t exposed to freezing temperatures for long periods of time.

Even if you live in an area where winters are mild, it’s important to protect your onion bulbs from extreme winter conditions because they may not be able to recover from a freeze once it’s happened.

How To Protect Your Onions From Frost

You can help protect your onions from frost by using various types of coverings. Here are some options to consider:

A row cover may be the easiest option. This is a lightweight fabric that you lay over plants that need to be covered in order to protect them from frost and wind. Row covers come in different weights, so make sure you get one that will work for your needs.

Another option is a floating row cover, which is similar to the standard row covers but has openings for ventilation so it doesn’t trap heat against the plant’s leaves as some other types do.

Mulch is another great way to keep cold temperatures from reaching your plants’ roots. Try using straw mulch or hay bales as insulation at night when temperatures drop below freezing; this will help prevent damage from occurring due to freezing temperatures overnight when soil heats up during daylight hours but then cools down again at nightfall once you remove those insulating materials away from around your plants’ roots where they would cause problems if left there all night long!

Caring For Onions During The Winter

Onions are hardy plants that can withstand temperatures as low as 32 degrees Fahrenheit before they freeze. However, when the temperature drops below freezing for long periods of time, it will kill the bulb’s roots and stop photosynthesis.

Here’s how to keep your onions alive through the winter:

Plant your onions in late summer or early fall so that they have time to mature before winter sets in.

Choose an area with full sun exposure with well-drained soil that has been amended with compost or manure prior to planting. The pH level should be 6.0 to 6.8; if it’s too high or too low, amend the soil accordingly using lime or sulfur before planting your onions.

Dig holes deep enough so that the bulbs are planted at least 3 inches below the surface of the ground; this will help prevent rot during cold weather by keeping them out of contact with wet soil and moisture from above-ground sources such as rainwater collecting on top of snow cover.

Can I Overwinter Onions?

Yes, it is possible to overwinter onions.

Onions are hardy vegetables that can be stored in an unheated garage or basement for up to six months.

When you store onions, it’s important that they are dry and have good ventilation. Keep them off the ground so they don’t get dirty. If you have onion storage bins or baskets, use them for this purpose.

How to Overwinter Onions:

Start by removing any leaves from the tops of your onions. You’ll want to be sure that there aren’t any leaf remnants on the bulb when you store them. This will help prevent potential rot from occurring during storage.

Next, remove any dirt from around the base of your bulbs and then cut off about 1/4 inch from their root end if they’re long-day varieties or 1/2 inch if they’re short-day varieties. You’ll want to make sure that the cuts are clean so that there’s no chance of infection occurring during storage (which would result in rotting).

After this, place your bulbs in a paper bag or cardboard box with some holes punched in it for air circulation, and then place it in a cool location like an unheated garage or basement.

When spring approaches, you can take them outside and plant them in your garden.


In conclusion, onions are a very hardy vegetable that can tolerate cold weather. However, they do need some protection from frost and freezing. You can plant your onion bulbs in the fall so that they will have time to grow before winter comes along. Also, you should cover them with mulch or straw in order to protect them from extreme temperatures. If you live in an area where temperatures drop below freezing often then consider growing these vegetables indoors instead!