When to Plant Coreopsis in Janesville, WI

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Janesville it's a good idea to determine when you can 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 can survive in mild cold which tells us that you can plant them a little earlier in the year than more sensitive plants.

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

The earliest that you can plant coreopsis in Janesville 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. If you wait any later than that and your coreopsis may not have a chance to grow to maturity. 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 all chance of frost has passed is on April 15 in Janesville. In the coldest months of winter you can expect an average low temperature of -20°F.

Remember that USDA zone info for Janesville is an average and the actual date of last frost will vary from year to year. Half of the time in Janesville last frost occurs after April 15 so be sure to be ready to cover your coreopsis if you have a surprise late frost.

USDA Zone Info for Janesville

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Janesville

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