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

A way of estimating when to plant runner beans is to examine the USDA zone info for Portland.

Planting Calendar for Runner beans

Frost tolerance for runner beans:	Not tolerant of frost.
When to plant:	After the last frost.

Since runner beans are not cold tolerant you need to wait until after the last frost before you can plant them.

The earliest that you can plant runner 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 runner beans and expect a good harvest is probably August. You probably don't want to wait any later than that or else your runner beans may not have a chance to grow to maturity. If you are starting your runner beans indoors then you might be able to get away with starting them a little bit earlier.

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.

Remember that USDA zone info for Portland is just an average and the actual date of last frost will vary from year to year. Half of the time in Portland last frost occurs after April 15 so make sure that you are prepared to protect your runner beans in the event of one of those late frosts.

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.