Before planting it is a good idea to find your USDA Zone info to determine your garden 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 Needles should be looked at to determine 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 a lot earlier in the year than more sensitive plants.

The earliest that you can plant purple rock cress in Needles is January. However, you really should wait until February 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 October. Any later than that and your purple rock cress may not have a chance to grow to maturity. 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 all chance of frost has passed is on February 15 in Needles. In the coldest months of winter you should expect an average low temperature of 25°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Needles and it can change quite a bit from year to year. Since half of the time in Needles last frost occurs after February 15 be ready to cover your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Needles

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Needles

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