When to Plant Onions in Richfield, UT

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when it's possible to plant onions is to use the USDA zone info for Richfield.


Planting Calendar for Onions

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

Since onions do well in cold you can plant them a lot earlier in the year than other plants that might not handle the cold.

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 Richfield 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 couple of weeks earlier.

Last Frost Date

In Richfield the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Richfield and it is different every year. Half of the time in Richfield it frosts late in the year after April 15 so always be ready to protect your onions if you have a late frost.

USDA Zone Info for Richfield

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Richfield

You may be interested in your other planting guides for Richfield.