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

The USDA zone info for Mercer Island should be reffered to in order to figure out 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 do ok in cold weather which means that you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant arabis in Mercer Island 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 fully mature. Starting your arabis indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Mercer Island. In the coldest months of winter you should expect an average low temperature of 15°F.

Remember that USDA zone info for Mercer Island is just an average and the actual date of last frost changes from year to year. Half of the time in Mercer Island it frosts late in the year after March 15 so make sure that you are prepared to cover your arabis in the event of a late frost.

USDA Zone Info for Mercer Island

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Mercer Island

You may be interested in your other planting guides for Mercer Island.