Before planting it is a good idea to find your USDA Zone info to estimate your garden 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 Harrisburg should be reviewed to estimate when it's a good idea to plant sweet potatos.

Planting Calendar for Sweet Potatos

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

Since sweet potatos are not cold tolerant you must wait until after the last frost when the weather gets warmer before you can plant them.

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

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Harrisburg and it changes from year to year. Half of the time in Harrisburg there is a last frost after April 15 so just be sure to be ready to cover your sweet potatos in the event of a surprise late frost.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Harrisburg

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