One of the best tools that you have as gardeners to help us figure out 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.

By checking out the USDA zone info for Portola Valley you should be able to estimate when you can plant carrots.

Planting Calendar for Carrots

Frost tolerance for carrots:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since carrots are moderately cold tolerant you can plant them just a bit earlier in the year than other frost tender plants.

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

Last Frost Date

The average date of last frost is January 31 in Portola Valley. It might get as low as 30°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Portola Valley and it will vary from year to year. Since half of the time in Portola Valley last frost occurs after January 31 be ready to protect your carrots in the event of 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.