One of the first steps you take when you are determining your gardening schedule is find your 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.

The best time to plant thyme in Mercer Island should be estimated by using the USDA zone info.

Planting Calendar for Thyme

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

You can plant thyme a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant thyme 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 thyme and expect a good harvest is probably September. If you wait any later than that and your thyme may not have a chance to grow to maturity. Starting your thyme indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Mercer Island the average date of last frost happens on March 15. You can expect an average low temperature of 15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Mercer Island is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Mercer Island you get a frost after March 15 be ready to protect your thyme if you have a late frost.

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.