When to Plant Sweet Potatos in Decatur, IL

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when to plant sweet potatos by referring to the USDA zone info for Decatur.


Planting Calendar for Sweet Potatos

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

You really shouldn't plant sweet potatos until after the last frost has passed because they are not cold tolerant.

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 Decatur 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 fully mature. If you are starting your sweet potatos indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Decatur. In the coldest months of winter you can expect an average low temperature of -15°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Decatur and it is different every year. Since half of the time in Decatur you get surprised by a frost after April 15 be ready to cover your sweet potatos in the event of a late frost.

USDA Zone Info for Decatur

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 Decatur

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