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

You should be able to estimate when you can plant purple rock cress by looking at the USDA zone info for Clearlake.

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 much earlier in the year because they do well in cold.

The earliest that you can plant purple rock cress in Clearlake 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 fully mature. 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

On average the last frost when the weather gets warmer is on March 15 in Clearlake. It might get as low as 15°F during the coldest months of winter.

It's important to remember that USDA zone info for Clearlake is an average and the actual date of last frost is different every year. Half of the time in Clearlake it frosts late in the year after March 15 so make sure that you are prepared to cover your purple rock cress if you have one of those late frosts.

USDA Zone Info for Clearlake

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 Clearlake

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