One of the first steps you take when you are determining 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 arabis in Walla Walla should be determined by reviewing the USDA zone info.

Planting Calendar for Arabis

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

Since arabis are one of those plants that can tolerate quite a bit of cold weather you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant arabis in Walla Walla 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 arabis and expect a good harvest is probably September. You probably don't want to wait any later than that or else your arabis may not have a chance to grow to maturity. 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 April 15 in Walla Walla. You should expect an average low temperature of 0°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Walla Walla and it changes from year to year. Half of the time in Walla Walla you get a frost after April 15 so just be sure to be ready to protect your arabis in the event of one of those late frosts.

USDA Zone Info for Walla Walla

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Walla Walla

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