One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to estimate when it's a good idea to plant pearl onions by looking at the USDA zone info for Fergus Falls.

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 a tiny bit of cold which tells us that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant pearl onions in Fergus Falls 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. If you wait any later than that and your pearl onions may not have a chance to grow to maturity. Starting your pearl onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Fergus Falls the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Fergus Falls and it will vary from year to year. Since half of the time in Fergus Falls it frosts late in the year after May 15 be ready to cover your pearl onions if you have a surprise late frost.

USDA Zone Info for Fergus Falls

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 Fergus Falls

You may be interested in your other planting guides for Fergus Falls.