The USDA Zone info is a great tool for gardeners to help us estimate 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.

You will be able to figure out when it's the best time to plant saxifraga by referring to the USDA zone info for San Francisco.

Planting Calendar for Saxifraga

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

You can plant saxifraga a bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant saxifraga in San Francisco 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 saxifraga and expect a good harvest is probably September. If you wait any later than that and your saxifraga may not have a chance to really do well. If you are starting your saxifraga indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In San Francisco the average date of last frost happens on January 31. It might get as low as 35°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for San Francisco and it is different every year. Since half of the time in San Francisco there is a last frost after January 31 be ready to cover your saxifraga if you have a surprise late frost.

USDA Zone Info for San Francisco

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in San Francisco

You may be interested in your other planting guides for San Francisco.