The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's a good idea to plant pearl onions is to look at the USDA zone info for Willmar.

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.

Pearl onions do ok in very little cold which tells us that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pearl onions in Willmar 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 really do well. You can get started a few weeks earlier by starting your pearl onions indoors.

Last Frost Date

The average date of last frost is May 15 in Willmar. It might get as low as -25°F during the coldest months of winter.

Remember that USDA zone info for Willmar is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Willmar it frosts late in the year after May 15 be ready to protect your pearl onions if you have a surprise late frost.

USDA Zone Info for Willmar

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Willmar

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