One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Washington you can estimate when it's possible to plant scarlet runner beans by referring to the USDA zone info.

Planting Calendar for Scarlet Runner Beans

Frost tolerance for scarlet runner beans:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Scarlet Runner Beans require warm weather which means that it's important to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant scarlet runner beans in Washington 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 scarlet runner beans and expect a good harvest is probably August. If you wait any later than that and your scarlet runner beans may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your scarlet runner beans indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Washington. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Washington is just an average the actual date of last frost is different every year. Half of the time in Washington last frost occurs after April 15 so always be ready to protect your scarlet runner beans in the event of one of those late frosts.

USDA Zone Info for Washington

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Washington

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