The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Wahpeton should be looked at to estimate when to 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.

Pearl onions can survive in mild cold which tells us that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pearl onions in Wahpeton 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. You can get started a couple of weeks earlier by starting your pearl onions indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Wahpeton. You can expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Wahpeton and it changes from year to year. Half of the time in Wahpeton it frosts late in the year after May 15 so make sure that you are prepared to cover your pearl onions in the event of a surprise late frost.

USDA Zone Info for Wahpeton

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 Wahpeton

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