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.

One way of figuring out when it's a good idea to plant spearmint is to examine the USDA zone info for Rockville.

Planting Calendar for Spearmint

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

Spearmint do ok in pretty solid cold which tells us that you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant spearmint in Rockville 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. Any later than that and your spearmint may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your spearmint indoors.

Last Frost Date

In Rockville the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 0°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Rockville and it will vary from year to year. Half of the time in Rockville you get a frost after April 15 so make sure that you are ready to cover your spearmint if you have a late frost.

USDA Zone Info for Rockville

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Rockville

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