When to Plant Asters in Wilmington, IL

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.

The USDA zone info for Wilmington can be read to estimate when it's possible to plant asters.


Planting Calendar for Asters

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

Asters are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them a little bit earlier than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant asters
Possibly ok, but a risky time to plant asters
Probably not a good time to plant asters

The earliest that you can plant asters in Wilmington 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. Any later than that and your asters may not have a chance to grow to maturity. If you are starting your asters indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Wilmington the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Wilmington is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Wilmington last frost occurs after April 15 be ready to cover your asters in the event of one of those late frosts.

USDA Zone Info for Wilmington

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 Wilmington

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