One of the best tools that you have as gardeners to help us figure out 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.

One way of determining when it's a good idea to plant common hollyhock is to examine the USDA zone info for Orinda.

Planting Calendar for Common hollyhock

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

Common hollyhock are moderately cold tolerant which means that you can get them planted earlier than more sensitive plants.

The earliest that you can plant common hollyhock in Orinda 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. You probably don't want to wait any later than that or else your common hollyhock may not have a chance to really do well. If you are starting your common hollyhock indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Orinda and it can change quite a bit from year to year. Since half of the time in Orinda it frosts late in the year after February 15 be ready to cover your common hollyhock in the event of a late frost.

USDA Zone Info for Orinda

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 Orinda

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