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.

The best time to plant common hollyhock in Downers Grove can be figured out by checking out the USDA zone info.

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 just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant common hollyhock in Downers Grove 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. Any later than that and 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

On average all chance of frost has passed is on April 15 in Downers Grove. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Downers Grove is just an average and the actual date of last frost will vary from year to year. Half of the time in Downers Grove it frosts late in the year after April 15 so be sure to be ready to protect your common hollyhock in the event of one of those late frosts.

USDA Zone Info for Downers Grove

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Downers Grove

You may be interested in your other planting guides for Downers Grove.