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

One way of getting a good idea when it's a good idea to plant common hollyhock is to look at the USDA zone info for Pleasanton.

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 just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant common hollyhock in Pleasanton 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. 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 few weeks earlier.

Last Frost Date

In Pleasanton 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.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Pleasanton and it changes from year to year. Half of the time in Pleasanton last frost occurs after February 15 so just be sure to be ready to cover your common hollyhock if you have one of those late frosts.

USDA Zone Info for Pleasanton

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 Pleasanton

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