The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when it's a good idea to plant spearmint by looking at the USDA zone info for Tomah.

Planting Calendar for Spearmint

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

Spearmint tend to make it in pretty solid cold which tells us that you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant spearmint in Tomah 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. If you wait any later than that and 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 little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Tomah. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Tomah may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Tomah you get a frost after May 15 so just be sure to be ready to protect your spearmint in the event of one of those late frosts.

USDA Zone Info for Tomah

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 Tomah

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