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

You should be able to estimate when it's possible to plant hollyhocks by referring to the USDA zone info for Placentia.

Planting Calendar for Hollyhocks

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

Hollyhocks are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than more sensitive plants.

The earliest that you can plant hollyhocks in Placentia 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. If you wait any later than that and your hollyhocks may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your hollyhocks indoors.

Last Frost Date

On average the last frost is on January 31 in Placentia. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Placentia may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Placentia it frosts late in the year after January 31 so make sure that you are ready to protect your hollyhocks in the event of a surprise late frost.

USDA Zone Info for Placentia

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Placentia

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