The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when to plant rock cress in Blue Island by reviewing 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.

You can plant rock cress much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant rock cress in Blue Island 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. You probably don't want to wait any later than that or else 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 couple of weeks earlier.

Last Frost Date

In Blue Island the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Just be sure to remember that USDA zone info for Blue Island is an average and the actual date of last frost changes from year to year. Half of the time in Blue Island it frosts late in the year after April 15 so make sure that you are ready to cover your rock cress in the event of one of those late frosts.

USDA Zone Info for Blue Island

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 Blue Island

You may be interested in your other planting guides for Blue Island.