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 USDA zone info for Portola Valley can be looked at to estimate when it's a good idea to plant schizanthus.

Planting Calendar for Schizanthus

Frost tolerance for schizanthus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You can not plant schizanthus until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant schizanthus 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 schizanthus and expect a good harvest is probably September. Any later than that and your schizanthus may not have a chance to really do well. If you are starting your schizanthus indoors then you might be able to get away with starting them 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.

Since the USDA zone info for Portola Valley may not be accurate from year to year 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 be sure to be ready to protect your schizanthus 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.