The USDA Zone info is a great tool for gardeners to help us determine 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.

The USDA zone info for Troy should be reviewed to estimate when it's a good idea to 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.

Since purple rock cress are very cold tolerant you can plant them much earlier in the year than more sensitive plants.

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

Last Frost Date

The average date of last frost is April 15 in Troy. It might get as low as -10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Troy is just an average and the actual date of last frost will vary from year to year. Half of the time in Troy there is a last frost after April 15 so always be ready to cover your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Troy

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 Troy

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