Before planting it is a good idea to find your USDA Zone info to estimate 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 best time to plant rock cress in Harrisburg can be figured out by using 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 do ok in a bit of cold which tells us that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant rock cress in Harrisburg 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. Any later than that and your rock cress may not have a chance to really do well. Starting your rock cress indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Harrisburg and it can change quite a bit from year to year. Half of the time in Harrisburg you get surprised by a frost after April 15 so be sure to be ready to protect your rock cress if you have one of those late frosts.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Harrisburg

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