When can I plant Spearmint in Zone 4a

One of the best tools that we have as gardeners to help us estimate our 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 our area.

The USDA zone info for Zone 4a should be looked at to determine when you can plant spearmint.


Planting Calendar for Spearmint

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

Since spearmint are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant spearmint
Possibly ok, but a risky time to plant spearmint
Probably not a good time to plant spearmint

The earliest that you can plant spearmint in Zone 4a 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 fully mature. Starting your spearmint indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 4a. We can expect an average low temperature of -30°F in the coldest months of winter.

Just be sure to remember that our actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Zone 4a and it changes from year to year. Since half of the time in Zone 4a we get surprised by a frost after May 15 be ready to protect your spearmint if we have a late frost.

USDA Zone Info for Zone 4a

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 Zone 4a

You may be interested in our other planting guides for Zone 4a.