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

In Oakland you can estimate when it's the best time to plant common hollyhock by referring to the USDA zone info.

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 one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than other frost tender plants.

The earliest that you can plant common hollyhock in Oakland is February. However, you really should wait until March 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 September. If you wait any later than that and 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 couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Oakland. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Oakland is an average the actual date of last frost changes from year to year. Since half of the time in Oakland it frosts late in the year after April 15 be ready to protect your common hollyhock if you have a late frost.

USDA Zone Info for Oakland

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Oakland

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