Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Portsmouth it's a good idea to determine when it's possible to plant thyme.

Planting Calendar for Thyme

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

Thyme do well in quite a bit of cold which tells us that you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant thyme in Portsmouth 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. You probably don't want to wait any later than that or else 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 Portsmouth the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Always keep in mind that USDA zone info for Portsmouth may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Portsmouth last frost occurs after March 15 so make sure that you are prepared to cover your thyme in the event of a late frost.

USDA Zone Info for Portsmouth

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Portsmouth

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