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 USDA zone info for Washington should be reviewed to determine when it's possible to plant morning glory.

Planting Calendar for Morning Glory

Frost tolerance for morning glory:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant morning glory until after all chance of frost has passed because they are not cold tolerant.

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

Last Frost Date

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

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 last frost occurs after April 15 so always be ready to protect your morning glory if you have a late frost.

USDA Zone Info for Washington

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 Washington

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