Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. 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 Watertown can be looked at to determine when it's a good idea to plant sweet potato vine.

Planting Calendar for Sweet Potato Vine

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

You can not plant sweet potato vine until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant sweet potato vine in Watertown 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

The average date of last frost is April 15 in Watertown. It might get as low as -20°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Watertown and it is different every year. Since half of the time in Watertown it frosts late in the year after April 15 be ready to protect your sweet potato vine in the event of a surprise late frost.

USDA Zone Info for Watertown

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Watertown

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