The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to determine when it's possible to plant larkspur by using the USDA zone info for Sonoma.

Planting Calendar for Larkspur

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

Larkspur do well in quite a bit of cold which tells us that you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant larkspur in Sonoma 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. Any later than that and your larkspur may not have a chance to grow to maturity. Starting your larkspur indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Sonoma the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that USDA zone info for Sonoma may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Sonoma last frost occurs after February 15 so always be ready to protect your larkspur if you have one of those late frosts.

USDA Zone Info for Sonoma

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 Sonoma

You may be interested in your other planting guides for Sonoma.