One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant purple bell vines in Portola Valley can be determined by reviewing the USDA zone info.

Planting Calendar for Purple Bell Vines

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

Purple Bell Vines are barely cold tolerant which tells us that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant purple bell vines 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 purple bell vines and expect a good harvest is probably September. You probably don't want to wait any later than that or else your purple bell vines may not have a chance to grow to maturity. Starting your purple bell vines indoors is a great way to get them started a couple of 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.

Since the USDA zone info for Portola Valley is not always accurate the actual date of last frost changes from year to year. Half of the time in Portola Valley last frost occurs after January 31 so just be sure to be ready to protect your purple bell vines 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.