One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Boston you can determine when it's the best time to plant spearmint by using the USDA zone info.

Planting Calendar for Spearmint

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

Spearmint do well in cold which means that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant spearmint in Boston is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant spearmint and expect a good harvest is probably September. You probably don't want to wait any later than that or else 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

In Boston the average date of last frost happens on April 15. You can expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember 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 Boston and it changes from year to year. Half of the time in Boston last frost occurs after April 15 so be sure to be ready to cover your spearmint in the event of a surprise late frost.

USDA Zone Info for Boston

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Boston

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