When to Plant Purple Rock Cress in Mattoon, IL

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

You can estimate when it's the best time to plant purple rock cress in Mattoon by reviewing the USDA zone info.


Planting Calendar for Purple Rock Cress

Frost tolerance for purple rock cress: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Purple Rock Cress are one of those plants that can tolerate quite a bit of cold weather which means that you can start planting them much earlier than more sensitive plants.

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

The earliest that you can plant purple rock cress in Mattoon 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 purple rock cress and expect a good harvest is probably September. You probably don't want to wait any later than that or else your purple rock cress may not have a chance to really do well. Starting your purple rock cress indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Mattoon. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Mattoon is an average the actual date of last frost changes from year to year. Half of the time in Mattoon you get surprised by a frost after April 15 so always be ready to protect your purple rock cress if you have a late frost.

USDA Zone Info for Mattoon

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Mattoon

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