One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Grand Haven you can figure out when to plant purple rock cress by checking out 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.

You can plant purple rock cress a lot 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 purple rock cress in Grand Haven 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. If you are starting your purple rock cress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Grand Haven. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that USDA zone info for Grand Haven is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Grand Haven you get a frost after April 15 be ready to cover your purple rock cress in the event of a late frost.

USDA Zone Info for Grand Haven

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 Grand Haven

You may be interested in your other planting guides for Grand Haven.