The USDA Zone info is a great tool for gardeners to help us determine 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.

By reviewing the USDA zone info for Chicago it's a good idea to figure out when it's a good idea 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.

Common hollyhock are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant common hollyhock in Chicago 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. If you wait any later than that and your common hollyhock may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your common hollyhock indoors.

Last Frost Date

The average date of last frost is April 15 in Chicago. You can expect an average low temperature of -10°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Chicago is an average and the actual date of last frost changes from year to year. Half of the time in Chicago it frosts late in the year after April 15 so just be sure to be ready to cover your common hollyhock in the event of a surprise late frost.

USDA Zone Info for Chicago

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Chicago

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