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.

In South San Francisco you can determine when it's the best time to plant hollyhocks by using the USDA zone info.

Planting Calendar for Hollyhocks

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

Hollyhocks are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than more sensitive plants.

The earliest that you can plant hollyhocks 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 hollyhocks and expect a good harvest is probably October. If you wait any later than that and your hollyhocks may not have a chance to fully mature. If you are starting your hollyhocks indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in South San Francisco. In the coldest months of winter you can expect an average low temperature of 30°F.

Remember that USDA zone info for South San Francisco is just an average and the actual date of last frost changes from year to year. Since half of the time in South San Francisco there is a last frost after January 31 be ready to protect your hollyhocks 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.