How to Grow Sweet Corn

When you grow your own sweet corn and eat them fresh, you won’t believe the difference in taste. 

Fresh Sweet Corn Sweeter Straight from Filed

Fresh Sweet Corn Sweeter Straight from Filed

Sweet corn is available virtually year round. It is best when picked and eaten fresh from the garden if possible, since the sugar starts turning to starch the minute it is picked.

©2011, Dorling Kindersley Limited

2011, Dorling Kindersley Limited

Materials Needed

  • sweet corn seeds of choice
  • well-drained soil
  • quick-growing catch cropseeds (optional)

Step 1: Sow Seed in Spring

Plant Sweet Corn in Blocks for Good Pollination

Plant Sweet Corn in Blocks for Good Pollination

Corn plants need to be close together for good pollination. Pollen is moved by breezes. Corn needs neighbors for pollination. Plant corn in blocks for successful crop.

©2011, Dorling Kindersley Limited

2011, Dorling Kindersley Limited

Sweet corn requires a hot season to produce a good crop, so plant in a sheltered, sunny site with well-drained soil. In colder areas, sow seed in the spring under cover in a heated propagator, set to a minimum temperature of 61–70 degrees F. To encourage good pollination, plant sweet corn in blocks, 18 inches apart, so the pollen can be blown by the wind from plant to plant. Baby corn can be planted more closely, 6 inches apart. Grow the seedlings at room temperature, and harden them off once the risk of frost has passed.

Step 2: Co-Plant With Other Crops

Co Plant Corn with Other Crops that Mature Faster

Co Plant Corn with Other Crops that Mature Faster

Sweet corn is ideal for under cropping, or growing other plants between them, because their foliage lets lots of light through. Examples of vegetables which will do well with sweet corn are dwarf French beans, radish, lettuce, or most small vegetables.

©2011, Dorling Kindersley Limited

2011, Dorling Kindersley Limited

Sweet corn is slow to develop, and young plants cast only light shade. Take advantage of the space below them as they develop, and underplant with a quick-growing catch crop, such as beets, radishes or kohlrabi.

Step 3: Test the Cobs

Check Corn Cob for Readiness By Testing Top Kernel

Check Corn Cob for Readiness By Testing Top Kernel

Sweetcorn is ready to harvest when the kernels are in the milk stage. There is a simple test that to check this. Puncture a kernel with thumbnail to make sure. If a clear liquid appears, then the corn is immature. If liquid is milky, then corn is ready.

©2011, Dorling Kindersley Limited

2011, Dorling Kindersley Limited

Leave late-season cobs to ripen as long as possible before the first frost. Check to see if cobs are ready by exposing the cob and pressing a fingernail into a kernel. If it exudes milky sap, it is ready to harvest. The minute a cob is picked, the sugar in the kernels starts turning to starch, reducing its tenderness and sweetness.