One of the first steps you take when you are making a decision about 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.

The earliest that you can plant purple rock cress in Hillsboro can be figured out by referring to 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.

Purple Rock Cress can survive in pretty solid cold which means that you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant purple rock cress in Hillsboro 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. You can get started a few weeks earlier by starting your purple rock cress indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Hillsboro. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Hillsboro is just an average the actual date of last frost is different every year. Since half of the time in Hillsboro there is a last frost after April 15 be ready to cover your purple rock cress in the event of a late frost.

USDA Zone Info for Hillsboro

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 Hillsboro

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