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.

In Zone 1a you can determine when you can plant arabis by checking out 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 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 1a is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant arabis and expect a good harvest is probably July. You probably don't want to wait any later than that or else your arabis may not have a chance to fully mature. You can get started a few weeks earlier by starting your arabis indoors.

Last Frost Date

On average all chance of frost has passed is on June 15 in Zone 1a. In the coldest months of winter you should expect an average low temperature of -60°F.

Keep in mind 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 Zone 1a and it changes from year to year. Half of the time in Zone 1a last frost occurs after June 15 so make sure that you are ready to protect your arabis if you have one of those late frosts.

USDA Zone Info for Zone 1a

Here is the info for USDA Zone 1a.

Average Date of Last Frost (spring)	June 15
Average Date of First Frost (fall)	July 15
Lowest Expected Low	-60°F
Highest Expected Low	-55°F

This means that on a really cold year, the coldest it will get is -60°F. On most years you should be prepared to experience lows near -55°F.

Plants to Grow in Zone 1a

You may be interested in your other planting guides for Zone 1a.