One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

You will be able to determine when to plant common hollyhock by looking at the USDA zone info for Walnut Creek.

Planting Calendar for Common hollyhock

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

You can plant common hollyhock a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant common hollyhock in Walnut Creek 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 common hollyhock and expect a good harvest is probably October. Any later than that and your common hollyhock may not have a chance to fully mature. Starting your common hollyhock indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Walnut Creek. You can expect an average low temperature of 25°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Walnut Creek and it is different every year. Since half of the time in Walnut Creek last frost occurs after February 15 be ready to protect your common hollyhock if you have one of those late frosts.

USDA Zone Info for Walnut Creek

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 Walnut Creek

You may be interested in your other planting guides for Walnut Creek.