One of the first steps you take when you are estimating your gardening schedule is find your 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 figuring out when you can plant common hollyhock is to use the USDA zone info for Colusa.

Planting Calendar for Common hollyhock

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

Since common hollyhock do well in moderate cold you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant common hollyhock in Colusa 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 fully mature. You can get started a few weeks earlier by starting your common hollyhock indoors.

Last Frost Date

In Colusa the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Colusa and it is different every year. Half of the time in Colusa last frost occurs after February 15 so make sure that you are ready to protect your common hollyhock if you have a late frost.

USDA Zone Info for Colusa

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 Colusa

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