When to Plant Sweet corn in Denison, IA

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Denison can be reffered to in order to figure out when it's a good idea to plant sweet corn.


Planting Calendar for Sweet corn

Frost tolerance for sweet corn: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Sweet corn do ok in very little cold which means that you can plant them slightly earlier in the year than more sensitive plants.

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

The earliest that you can plant sweet corn in Denison is March. However, you really should wait until April if you don't want to take any chances.

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

Last Frost Date

In Denison the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Keep in mind that USDA zone info for Denison is just an average and the actual date of last frost changes from year to year. Half of the time in Denison you get surprised by a frost after April 15 so always be ready to protect your sweet corn in the event of a late frost.

USDA Zone Info for Denison

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Denison

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