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

A way of getting a good idea when to plant purple coneflower is to use the USDA zone info for Joliet.

Planting Calendar for Purple Coneflower

Frost tolerance for purple coneflower:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Purple Coneflower are one of those plants that can tolerate a tiny bit of cold weather which means that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant purple coneflower in Joliet is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant purple coneflower and expect a good harvest is probably August. Any later than that and your purple coneflower may not have a chance to really do well. You can get started a few weeks earlier by starting your purple coneflower indoors.

Last Frost Date

The average date of last frost is April 15 in Joliet. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Joliet is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Joliet it frosts late in the year after April 15 so always be ready to protect your purple coneflower in the event of a late frost.

USDA Zone Info for Joliet

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 Joliet

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