When to Plant Pearl onions in Duluth, MN

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.

The USDA zone info for Duluth can be used to estimate when you can plant pearl onions.


Planting Calendar for Pearl onions

Frost tolerance for pearl onions: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

You can plant pearl onions just a tiny bit earlier in the year because they are barely cold tolerant.

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

The earliest that you can plant pearl onions in Duluth is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant pearl onions and expect a good harvest is probably August. Any later than that and your pearl onions may not have a chance to fully mature. Starting your pearl onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Duluth. In the coldest months of winter you can expect an average low temperature of -30°F.

Always keep in mind that USDA zone info for Duluth is an average and the actual date of last frost changes from year to year. Since half of the time in Duluth it frosts late in the year after May 15 be ready to protect your pearl onions in the event of a surprise late frost.

USDA Zone Info for Duluth

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Duluth

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