When to Plant Potatos in Sullivan, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's a good idea to plant potatos is to examine the USDA zone info for Sullivan.


Planting Calendar for Potatos

Frost tolerance for potatos: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Since potatos are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than more sensitive plants.

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

The earliest that you can plant potatos in Sullivan is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant potatos and expect a good harvest is probably September. You probably don't want to wait any later than that or else your potatos may not have a chance to fully mature. You can get started a little bit earlier by starting your potatos indoors.

Last Frost Date

The average date of last frost is April 15 in Sullivan. You can expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Sullivan may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Sullivan there is a last frost after April 15 be ready to cover your potatos if you have a late frost.

USDA Zone Info for Sullivan

Here is the info for USDA Zone 6a.

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

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Sullivan

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