When to Plant Onions in Colorado Springs, CO

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when you can plant onions by referring to the USDA zone info for Colorado Springs.


Planting Calendar for Onions

Frost tolerance for onions: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

You can plant onions a lot earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant onions
Possibly ok, but a risky time to plant onions
Probably not a good time to plant onions

The earliest that you can plant onions in Colorado Springs is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant onions and expect a good harvest is probably September. You probably don't want to wait any later than that or else your onions may not have a chance to really do well. Starting your onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Colorado Springs the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Colorado Springs is not always accurate the actual date of last frost is different every year. Since half of the time in Colorado Springs you get surprised by a frost after April 15 be ready to cover your onions if you have a late frost.

USDA Zone Info for Colorado Springs

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Colorado Springs

You may be interested in your other planting guides for Colorado Springs.