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

A common way of making a decision about when it's the best time to plant sweet potato vine is to consult the USDA zone info for Portsmouth.

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.

Since sweet potato vine are not cold tolerant it's necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant sweet potato vine in Portsmouth 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 fully mature. If you are starting your sweet potato vine indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Portsmouth. It might get as low as -5°F during the coldest months of winter.

Remember that USDA zone info for Portsmouth may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Portsmouth you get a frost after April 15 so make sure that you are ready to cover your sweet potato vine if you have a late frost.

USDA Zone Info for Portsmouth

Here is the info for USDA Zone 6b.

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

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Portsmouth

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