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

By looking at the USDA zone info for Alhambra it's possible to estimate when it's a good idea to plant rock cress.

Planting Calendar for Rock Cress

Frost tolerance for rock cress:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Rock Cress do well in pretty solid cold which tells us that you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant rock cress in Alhambra 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 rock cress and expect a good harvest is probably October. Any later than that and your rock cress may not have a chance to fully mature. If you are starting your 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 January 31 in Alhambra. In the coldest months of winter you can expect an average low temperature of 30°F.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Alhambra and it is different every year. Half of the time in Alhambra you get surprised by a frost after January 31 so just be sure to be ready to protect your rock cress if you have a late frost.

USDA Zone Info for Alhambra

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Alhambra

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