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.

You can estimate when you can plant asters in Joliet by looking at the USDA zone info.

Planting Calendar for Asters

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

Since asters are moderately cold tolerant you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant asters in Joliet 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 asters and expect a good harvest is probably September. If you wait any later than that and your asters may not have a chance to fully mature. Starting your asters indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Joliet the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Joliet is not always accurate the actual date of last frost changes from year to year. Since half of the time in Joliet it frosts late in the year after April 15 be ready to protect your asters in the event of one of those late frosts.

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.