Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant purple rock cress in Louisville should be estimated by looking at 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 do ok in pretty solid cold which means that you can plant them quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant purple rock cress in Louisville 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 really do well. You can get started a little bit earlier by starting your purple rock cress indoors.

Last Frost Date

On average the last frost is on April 15 in Louisville. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Louisville is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Louisville last frost occurs after April 15 so just be sure to be ready to cover your purple rock cress if you have a late frost.

USDA Zone Info for Louisville

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 Louisville

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