One of the first steps you take when you are estimating 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.

You can determine when it's possible to plant sweet potato vine in Mercer Island by using 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 has passed.

Sweet Potato Vine are not cold tolerant which means that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant sweet potato vine in Mercer Island 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. Any later than that and your sweet potato vine may not have a chance to really do well. If you are starting your sweet potato vine indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on March 15 in Mercer Island. It might get as low as 15°F during the coldest months of winter.

Always keep in mind that USDA zone info for Mercer Island is just an average and the actual date of last frost is different every year. Half of the time in Mercer Island it frosts late in the year after March 15 so be sure to be ready to protect your sweet potato vine if you have one of those late frosts.

USDA Zone Info for Mercer Island

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Mercer Island

You may be interested in your other planting guides for Mercer Island.