One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant sweet potato vine in Washington can be determined by reviewing the USDA zone info.

Planting Calendar for Sweet Potato Vine

Frost tolerance for sweet potato vine:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You can not plant sweet potato vine until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant sweet potato vine 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 sweet potato vine and expect a good harvest is probably August. If you wait any later than that and your sweet potato vine may not have a chance to fully mature. You can get started a few weeks earlier by starting your sweet potato vine indoors.

Last Frost Date

In Washington the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 0°F.

Since the USDA zone info for Washington may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Washington it frosts late in the year after April 15 be ready to protect your sweet potato vine in the event of a late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°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.