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

By looking at the USDA zone info for Stewartville it's a good idea to estimate when it's the best time to plant spearmint.

Planting Calendar for Spearmint

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

Since spearmint are very cold tolerant you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant spearmint in Stewartville 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. Any later than that and your spearmint may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your spearmint indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Stewartville. It might get as low as -25°F during the coldest months of winter.

Remember that USDA zone info for Stewartville is an average and the actual date of last frost will vary from year to year. Since half of the time in Stewartville last frost occurs after May 15 be ready to protect your spearmint in the event of a surprise late frost.

USDA Zone Info for Stewartville

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 Stewartville

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