One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

It's a good idea to figure out when it's a good idea to plant purple rock cress by looking at the USDA zone info for Keokuk.

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 very cold tolerant which means that you can plant them a quite a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant purple rock cress in Keokuk 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. If you wait any later than that and your purple rock cress may not have a chance to fully mature. If you are starting your purple rock cress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Keokuk. It might get as low as -10°F during the coldest months of winter.

It's important to remember that USDA zone info for Keokuk is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Keokuk last frost occurs after April 15 so be sure to be ready to protect your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Keokuk

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 Keokuk

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