One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 Douglas should be figured out by looking at 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.

Arabis are very cold tolerant which means that you can get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant arabis in Douglas is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant arabis and expect a good harvest is probably August. If you wait any later than that and your arabis may not have a chance to grow to maturity. If you are starting your arabis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Douglas the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Douglas is just an average the actual date of last frost changes from year to year. Since half of the time in Douglas there is a last frost after May 15 be ready to protect your arabis if you have a late frost.

USDA Zone Info for Douglas

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Douglas

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