Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Clarendon Hills you will be able to estimate when it's possible to plant coreopsis.

Planting Calendar for Coreopsis

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

Coreopsis do ok in mild cold which tells us that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant coreopsis in Clarendon Hills 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 coreopsis and expect a good harvest is probably September. You probably don't want to wait any later than that or else your coreopsis may not have a chance to really do well. If you are starting your coreopsis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Clarendon Hills. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Clarendon Hills is just an average the actual date of last frost is different every year. Since half of the time in Clarendon Hills it frosts late in the year after April 15 be ready to cover your coreopsis if you have a surprise late frost.

USDA Zone Info for Clarendon Hills

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 Clarendon Hills

You may be interested in your other planting guides for Clarendon Hills.