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

In Portola Valley you can determine when it's possible to plant thyme by reviewing 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.

Thyme are very cold tolerant which tells us that you can plant them much earlier than more sensitive plants.

The earliest that you can plant thyme in Portola Valley is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant thyme and expect a good harvest is probably October. If you wait any later than that and your thyme may not have a chance to grow to maturity. If you are starting your thyme indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Portola Valley the average date of last frost happens on January 31. You can expect an average low temperature of 30°F in the coldest months of winter.

Remember that USDA zone info for Portola Valley is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Portola Valley it frosts late in the year after January 31 be ready to protect your thyme if you have a surprise late frost.

USDA Zone Info for Portola Valley

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Portola Valley

You may be interested in your other planting guides for Portola Valley.