One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for South San Francisco should be looked at to estimate when it's a good idea to plant borage.

Planting Calendar for Borage

Frost tolerance for borage:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Borage are moderately cold tolerant which means that you can get them planted earlier than plants that are more sensitive to the cold.

The earliest that you can plant borage in South 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 borage and expect a good harvest is probably October. If you wait any later than that and your borage may not have a chance to grow to maturity. If you are starting your borage indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in South San Francisco. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for South San Francisco is an average the actual date of last frost will vary from year to year. Half of the time in South San Francisco last frost occurs after January 31 so always be ready to cover your borage if you have a late frost.

USDA Zone Info for South San Francisco

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 South San Francisco

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