Before planting it is a good idea to find your USDA Zone info to estimate 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 first opportunity to plant hardy asters in Lisle can be estimated by checking out the USDA zone info.

Planting Calendar for Hardy Asters

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

Hardy Asters do ok in some cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant hardy asters in Lisle 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 hardy asters and expect a good harvest is probably August. You probably don't want to wait any later than that or else your hardy asters may not have a chance to fully mature. You can get started a few weeks earlier by starting your hardy asters indoors.

Last Frost Date

The average date of last frost is April 15 in Lisle. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Lisle is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Lisle there is a last frost after April 15 be ready to protect your hardy asters if you have a late frost.

USDA Zone Info for Lisle

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 Lisle

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