Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for San Francisco it's possible to figure out when to plant arabis.

Planting Calendar for Arabis

Frost tolerance for arabis:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Arabis tend to make it in pretty solid cold which tells us that you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant arabis in San Francisco is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant arabis and expect a good harvest is probably October. Any later than that and your arabis may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your arabis indoors.

Last Frost Date

On average the last frost is on January 31 in San Francisco. It might get as low as 35°F during the coldest months of winter.

Keep in mind that USDA zone info for San Francisco is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in San Francisco last frost occurs after January 31 so always be ready to protect your arabis in the event of one of those late frosts.

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.