The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 determining when it's possible to plant hollyhocks is to check out the USDA zone info for San Jose.

Planting Calendar for Hollyhocks

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

Hollyhocks do ok in mild cold which tells us that you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant hollyhocks in San Jose 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. You probably don't want to wait any later than that or else your hollyhocks may not have a chance to really do well. You can get started a few weeks earlier by starting your hollyhocks indoors.

Last Frost Date

In San Jose 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 San Jose and it will vary from year to year. Since half of the time in San Jose you get a frost after February 15 be ready to protect your hollyhocks in the event of a surprise late frost.

USDA Zone Info for San Jose

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 San Jose

You may be interested in your other planting guides for San Jose.