One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of getting a good idea when you can plant alyssum is to consult the USDA zone info for International Falls.

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 a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant alyssum in International Falls 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. Any later than that and your alyssum may not have a chance to fully mature. You can get started a little bit earlier by starting your alyssum indoors.

Last Frost Date

On average the last frost is on May 15 in International Falls. You can expect an average low temperature of -40°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for International Falls and it can change quite a bit from year to year. Half of the time in International Falls there is a last frost after May 15 so be sure to be ready to cover your alyssum in the event of a late frost.

USDA Zone Info for International Falls

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-40°F
Highest Expected Low	-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in International Falls

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