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 San Francisco can be read to determine when to plant scabiosa.

Planting Calendar for Scabiosa

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

Since scabiosa are one of those plants that can tolerate a little bit of cold weather you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant scabiosa 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 scabiosa and expect a good harvest is probably October. Any later than that and your scabiosa may not have a chance to really do well. You can get started a couple of weeks earlier by starting your scabiosa indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in San Francisco. You should expect an average low temperature of 35°F in the coldest months of winter.

Since the USDA zone info for San Francisco is just an average the actual date of last frost is different every year. Since half of the time in San Francisco you get a frost after January 31 be ready to cover your scabiosa in the event of a 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.