When to Plant Purple Coneflower in Harrisburg, IL

One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Harrisburg should be reffered to in order to figure out when it's possible to plant purple coneflower.


Planting Calendar for Purple Coneflower

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

Since purple coneflower are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than other plants that might not handle the cold.

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

The earliest that you can plant purple coneflower in Harrisburg 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 purple coneflower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your purple coneflower may not have a chance to grow to maturity. Starting your purple coneflower indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Harrisburg. It might get as low as -5°F during the coldest months of winter.

Remember that USDA zone info for Harrisburg is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Harrisburg you get a frost after April 15 be ready to cover your purple coneflower if you have a surprise late frost.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Harrisburg

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