The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant creeping zinnia in Portola Valley should be estimated by reviewing the USDA zone info.

Planting Calendar for Creeping Zinnia

Frost tolerance for creeping zinnia:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Creeping Zinnia do ok in some cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant creeping zinnia 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 creeping zinnia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your creeping zinnia may not have a chance to grow to maturity. If you are starting your creeping zinnia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on January 31 in Portola Valley. It might get as low as 30°F during 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 it frosts late in the year after January 31 so make sure that you are prepared to cover your creeping zinnia in the event of one of those late frosts.

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.