One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

The USDA zone info for Washington can be read to determine when it's possible to plant string beans.

Planting Calendar for String beans

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

You should not plant string beans until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant string 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 string beans and expect a good harvest is probably August. Any later than that and your string beans may not have a chance to really do well. Starting your string beans indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Washington is just an average the actual date of last frost will vary from year to year. Half of the time in Washington it frosts late in the year after April 15 so be sure to be ready to protect your string beans in the event of a late frost.

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.