When to Plant Rock Cress in Downers Grove, IL

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant rock cress in Downers Grove should be figured out by looking at the USDA zone info.


Planting Calendar for Rock Cress

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

Rock Cress are very cold tolerant which means that you can plant them a quite a bit earlier than other frost tender plants.

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

The earliest that you can plant rock cress in Downers Grove 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 rock cress and expect a good harvest is probably September. If you wait any later than that and your rock cress may not have a chance to fully mature. If you are starting your rock cress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Downers Grove the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Downers Grove is just an average the actual date of last frost is different every year. Half of the time in Downers Grove you get a frost after April 15 so be sure to be ready to cover your rock cress if you have a late frost.

USDA Zone Info for Downers Grove

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 Downers Grove

You may be interested in your other planting guides for Downers Grove.