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

By using the USDA zone info for Grand Forks it's possible to figure out when you can plant erysimum.

Planting Calendar for Erysimum

Frost tolerance for erysimum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Erysimum do ok in moderate cold which tells us that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant erysimum in Grand Forks is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant erysimum and expect a good harvest is probably August. Any later than that and your erysimum may not have a chance to grow to maturity. If you are starting your erysimum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Grand Forks. You should expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Grand Forks is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Grand Forks there is a last frost after May 15 be ready to cover your erysimum if you have a late frost.

USDA Zone Info for Grand Forks

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 Grand Forks

You may be interested in your other planting guides for Grand Forks.