When to Plant Sunflowers in Decatur, IL

One of the first steps you take when you are getting a good idea your gardening schedule is find your 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 can determine when it's possible to plant sunflowers in Decatur by referring to the USDA zone info.


Planting Calendar for Sunflowers

Frost tolerance for sunflowers: Not tolerant of frost.
When to plant: After all chance of frost has passed.

You should not plant sunflowers until after the last frost because they do not do well in cold weather.

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

The earliest that you can plant sunflowers 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 sunflowers and expect a good harvest is probably August. If you wait any later than that and your sunflowers may not have a chance to really do well. Starting your sunflowers indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Decatur is just an average and the actual date of last frost changes from year to year. Since half of the time in Decatur there is a last frost after April 15 be ready to cover your sunflowers if you have 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.