The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

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

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 can survive in some cold which means that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant common hollyhock in Santa Clara 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. Any later than that and your common hollyhock may not have a chance to fully mature. 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

In Santa Clara the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Keep in mind that USDA zone info for Santa Clara may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Santa Clara it frosts late in the year after March 15 so always be ready to cover your common hollyhock if you have a surprise late frost.

USDA Zone Info for Santa Clara

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Santa Clara

You may be interested in your other planting guides for Santa Clara.