One of the best tools that you have as gardeners to help us figure out 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.

The USDA zone info for Grand Forks should be reviewed to estimate when it's possible to plant alyssum.

Planting Calendar for Alyssum

Frost tolerance for alyssum:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant alyssum quite a bit earlier in the year because they are very cold tolerant.

The earliest that you can plant alyssum 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 alyssum and expect a good harvest is probably August. If you wait any later than that and your alyssum may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your alyssum indoors.

Last Frost Date

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

Since the USDA zone info for Grand Forks is just an average the actual date of last frost changes from year to year. Half of the time in Grand Forks it frosts late in the year after May 15 so make sure that you are ready to protect your alyssum in the event of one of those late frosts.

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.