When to Plant Sweet Potatos in Marengo, IL

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant sweet potatos in Marengo should be estimated by reviewing the USDA zone info.


Planting Calendar for Sweet Potatos

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

Sweet Potatos are not cold tolerant which tells us that it's important to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant sweet potatos
Possibly ok, but a risky time to plant sweet potatos
Probably not a good time to plant sweet potatos

The earliest that you can plant sweet potatos in Marengo 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. You probably don't want to wait any later than that or else your sweet potatos may not have a chance to fully mature. If you are starting your sweet potatos indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Marengo. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Marengo is just an average the actual date of last frost will vary from year to year. Half of the time in Marengo there is a last frost after April 15 so always be ready to protect your sweet potatos in the event of a late frost.

USDA Zone Info for Marengo

Here is the info for USDA Zone 5b.

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

Plants to Grow in Marengo

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