Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Costa Mesa it's possible to determine when it's the best time to plant common hollyhock.

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 a little 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 Costa Mesa 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. Any later than that and your common hollyhock may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your common hollyhock indoors.

Last Frost Date

In Costa Mesa the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 35°F.

Just be sure to remember that USDA zone info for Costa Mesa is just an average and the actual date of last frost will vary from year to year. Since half of the time in Costa Mesa there is a last frost after January 31 be ready to protect your common hollyhock in the event of a surprise late frost.

USDA Zone Info for Costa Mesa

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Costa Mesa

You may be interested in your other planting guides for Costa Mesa.