When to Plant Marigold in Decatur, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden 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 marigold in Decatur should be determined by referring to the USDA zone info.


Planting Calendar for Marigold

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

Marigold are not cold tolerant which tells us that you really should wait until it warms up after the last frost has passed before you can plant them.

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

The earliest that you can plant marigold 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 marigold and expect a good harvest is probably August. You probably don't want to wait any later than that or else your marigold may not have a chance to fully mature. Starting your marigold indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Decatur. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Decatur is just an average the actual date of last frost changes from year to year. Half of the time in Decatur last frost occurs after April 15 so be sure to be ready to cover your marigold in the event of a surprise 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.