Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant hollyhocks in Collinsville by reviewing the USDA zone info.

Planting Calendar for Hollyhocks

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

Hollyhocks do ok in moderate cold which means that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant hollyhocks in Collinsville 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 hollyhocks and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hollyhocks may not have a chance to really do well. Starting your hollyhocks indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Collinsville. You can expect an average low temperature of 0°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Collinsville is an average and the actual date of last frost changes from year to year. Half of the time in Collinsville you get a frost after April 15 so be sure to be ready to protect your hollyhocks if you have a late frost.

USDA Zone Info for Collinsville

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Collinsville

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