Sweet Corn - Illinois Vegetable Garden Guide - University of Illinois Extension

Sweet Corn

sweet corn

If you want a constant supply of sweet corn throughout the summer until frost occurs, include an early (67 to 72days to maturity) and a main-crop (78 to 83 days to maturity) variety in the first planting and then follow with a succession of plantings of a main-crop variety. The second planting is made when 3 leaves are present on the seedlings in the previous planting.

Plant two or more rows of sweet corn side by side to insure good pollination and development of ears. Plantings can be made until the first week of July. Keep weeds under control by shallow cultivation. Removal of "suckers" or side shoots is not recommended.

The main diseases of sweet corn are smut and Stewart's disease (bacterial wilt). Damage from Stewart's disease can be reduced by using varieties partially resistant to this disease and by controlling flea beetles (which carry the bacteria that cause the disease) when the plants first come through the soil.

sweet corn

Corn borers, corn earworms, and flea beetles are the chief insects to be controlled in sweet corn. Proper timing in applying insecticides is important if you want worm-free corn.

For sweet, plump kernels harvest sweet corn when it is in the milk stage; that is, when the juice in the kernel appears milky when you puncture the kernel with your thumbnail. Sweet corn remains in the milk stage for a relatively short period. As harvest approaches,check the corn frequently to make sure that the kernels do not become over mature and doughy. Other signs that indicate that the corn is almost ready for harvest are drying of the silks, fullness of the tip kernels, and firmness of the ear.

Eat, can, or freeze the corn immediately after picking or refrigerate it until used. At high temperatures the sugar in sweet corn quickly decreases and the starch increases.

Crop Amount for 100
ft of row
Variety recommended for use in Illinois Days to harvest Resistant to
Corn, Sweet (seed) 1-2 ounces Standard
Iochief 86
Jubilee 82
Platinum Lady 86
Silver Queen 92
Bi Queen 92
Honey and Cream 80
Sugary Enhancer Hybrids
Bodacious 72
Kandy Korn 89
Maple Sweet 70
Spring Treat 67
Cotton Candy 72
Snowbelle 79
Spring Snow 65
Sugar Snow 71
Supersweet Hybrids
Challenger 76
Early Xtra Sweet 70
Illini Gold 79
Illini Xtra Sweet 85
Honey 'N Pearl 78
Vegetable Hardiness Recommended planting period for central Illinois (b) Time to grow from seed to field (c)
For  overall
Corn, sweet 1-2 in row
4-6 per hill
9-12, single plants
36, hills (3 plants per hill)
24-48 1-2
Vegetable Spacing in row
Seed to sow per foot Distance between plants when thinned or transplanted Distance between rows Planting depth
inches inches inches
Corn, sweet 1-2 in row
4-6 per hill
9-12, single plants
36, hills (3 plants per hill)
24-48 1-2