One of the first steps you take when you are estimating 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.

The first chance to plant hollyhocks in Sonoma can be figured out by checking out 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 tells us that you can get them planted earlier than other plants that might not handle the cold.

The earliest that you can plant hollyhocks 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 hollyhocks and expect a good harvest is probably October. Any later than that and your hollyhocks may not have a chance to really do well. 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 the last frost is on February 15 in Sonoma. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Sonoma may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Sonoma there is a last frost after February 15 so be sure to be ready to cover your hollyhocks 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.