The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant arabis in Portland should be estimated by using 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.

You can plant arabis a lot earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant arabis in Portland 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. Any later than that and your arabis may not have a chance to really do well. You can get started a couple of weeks earlier by starting your arabis indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Portland. It might get as low as -15°F during the coldest months of winter.

It's important to remember 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 Portland and it changes from year to year. Since half of the time in Portland last frost occurs after April 15 be ready to cover your arabis if you have a late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Portland

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