One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 purple rock cress in Park Forest should be determined by referring to 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 plant them much earlier than other plants that might not handle the cold.

The earliest that you can plant purple rock cress in Park Forest 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. Any later than that and your purple rock cress may not have a chance to really do well. You can get started a little bit earlier by starting your purple rock cress indoors.

Last Frost Date

The average date of last frost is April 15 in Park Forest. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that USDA zone info for Park Forest is an average and the actual date of last frost will vary from year to year. Half of the time in Park Forest there is a last frost after April 15 so always be ready to cover your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Park Forest

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 Park Forest

You may be interested in your other planting guides for Park Forest.