One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when you can plant purple rock cress by referring to the USDA zone info for Troutdale.

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 earlier in the year than other frost tender plants.

The earliest that you can plant purple rock cress in Troutdale 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 really do well. You can get started a little bit earlier by starting your purple rock cress indoors.

Last Frost Date

In Troutdale the average date of last frost happens on March 15. It might get as low as 15°F during the coldest months of winter.

It's important to remember that USDA zone info for Troutdale is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Troutdale it frosts late in the year after March 15 be ready to protect your purple rock cress if you have a late frost.

USDA Zone Info for Troutdale

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

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

Plants to Grow in Troutdale

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