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.

It's possible to estimate when it's possible to plant celosia by looking at the USDA zone info for Portola Valley.

Planting Calendar for Celosia

Frost tolerance for celosia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You can not plant celosia until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant celosia in Portola Valley 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 celosia and expect a good harvest is probably September. Any later than that and your celosia may not have a chance to grow to maturity. If you are starting your celosia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on January 31 in Portola Valley. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Portola Valley is not always accurate the actual date of last frost will vary from year to year. Half of the time in Portola Valley last frost occurs after January 31 so make sure that you are prepared to protect your celosia if you have a 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.