Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of determining when it's a good idea to plant spearmint is to refer to the USDA zone info for Pierre.

Planting Calendar for Spearmint

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

Spearmint are one of those plants that can tolerate quite a bit of cold weather 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 Pierre 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 fully mature. 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

In Pierre the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Remember that USDA zone info for Pierre is not always accurate and the actual date of last frost is different every year. Half of the time in Pierre last frost occurs after May 15 so always be ready to cover your spearmint in the event of a late frost.

USDA Zone Info for Pierre

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Pierre

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