One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 Zone 9a should be looked at to determine when to plant arabis.

Planting Calendar for Arabis

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

Arabis can survive in quite a bit of cold which tells us that you can plant them quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant arabis in Zone 9a 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 arabis and expect a good harvest is probably October. If you wait any later than that and your arabis may not have a chance to really do well. You can get started a few weeks earlier by starting your arabis indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Zone 9a. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Zone 9a is just an average the actual date of last frost is different every year. Half of the time in Zone 9a there is a last frost after February 15 so always be ready to protect your arabis if you have a late frost.

USDA Zone Info for Zone 9a

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Zone 9a

You may be interested in your other planting guides for Zone 9a.