The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Kasson you should be able to estimate when you can plant purple rock cress.

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.

You can plant purple rock cress a lot earlier in the year because they do well in cold.

The earliest that you can plant purple rock cress in Kasson is March. However, you really should wait until April 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 August. If you wait any later than that and your purple rock cress may not have a chance to really do well. If you are starting your purple 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 May 15 in Kasson. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Kasson is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Kasson you get surprised by a frost after May 15 so make sure that you are ready to cover your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Kasson

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Kasson

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