The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when you can plant spearmint in Mercer Island 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.

You can plant spearmint a lot earlier in the year because they do well in cold.

The earliest that you can plant spearmint in Mercer Island 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 really do well. You can get started a little bit earlier by starting your spearmint indoors.

Last Frost Date

The average date of last frost is March 15 in Mercer Island. In the coldest months of winter you should expect an average low temperature of 15°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Mercer Island and it can change quite a bit from year to year. Since half of the time in Mercer Island you get surprised by a frost after March 15 be ready to protect your spearmint if you have one of those late frosts.

USDA Zone Info for Mercer Island

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Mercer Island

You may be interested in your other planting guides for Mercer Island.