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.

One way of getting a good idea when it's a good idea to plant rock cress is to look at the USDA zone info for Yankton.

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 do well in cold.

The earliest that you can plant rock cress in Yankton 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

The average date of last frost is April 15 in Yankton. You should expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that USDA zone info for Yankton is just an average and the actual date of last frost is different every year. Since half of the time in Yankton last frost occurs after April 15 be ready to protect your rock cress if you have a late frost.

USDA Zone Info for Yankton

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Yankton

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