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.

The first opportunity to plant pole beans in Portland should be estimated by using the USDA zone info.

Planting Calendar for Pole beans

Frost tolerance for pole beans:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since pole beans do not do well in cold weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant pole beans in Portland is April. However, you really should wait until May if you don't want to take any chances.

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

Last Frost Date

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

Keep in mind that USDA zone info for Portland is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Portland you get surprised by a frost after April 15 be ready to cover your pole beans if you have a surprise 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.