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.

A common way of getting a good idea when you can plant bougainvillea is to check out the USDA zone info for Portola Valley.

Planting Calendar for Bougainvillea

Frost tolerance for bougainvillea:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably not a good idea to plant bougainvillea until after the last frost when the weather gets warmer because they are not cold tolerant.

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

Last Frost Date

On average the last frost when the weather gets warmer 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 may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Portola Valley there is a last frost after January 31 so always be ready to protect your bougainvillea 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.