One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's a good idea to plant larkspur by using the USDA zone info for San Ramon.

Planting Calendar for Larkspur

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

Larkspur are very cold tolerant which means that you can plant them much earlier than more sensitive plants.

The earliest that you can plant larkspur in San Ramon 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 larkspur and expect a good harvest is probably October. If you wait any later than that and your larkspur may not have a chance to really do well. You can get started a little bit earlier by starting your larkspur indoors.

Last Frost Date

In San Ramon the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for San Ramon is an average and the actual date of last frost changes from year to year. Since half of the time in San Ramon last frost occurs after February 15 be ready to cover your larkspur if you have a surprise late frost.

USDA Zone Info for San Ramon

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in San Ramon

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