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

By looking at the USDA zone info for Dickinson you will be able to determine when you can plant spearmint.

Planting Calendar for Spearmint

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

Spearmint are very cold tolerant which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant spearmint in Dickinson 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 spearmint and expect a good harvest is probably August. You probably don't want to wait any later than that or else your spearmint may not have a chance to grow to maturity. If you are starting your spearmint 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 Dickinson. In the coldest months of winter you should expect an average low temperature of -30°F.

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 Dickinson and it is different every year. Since half of the time in Dickinson it frosts late in the year after May 15 be ready to protect your spearmint in the event of a surprise late frost.

USDA Zone Info for Dickinson

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 Dickinson

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