Sweet Corn

Sweet corn is an annual with yellow, white, and bi-colored ears. A long, frost-free growing season is necessary after planting. Sweet corn is wind-pollinated, so it should be planted in blocks, rather than in single rows. Early, mid, and late-season varieties extend the harvest. If you miss the optimal harvest time, corn will go downhill fast as sugars convert to starch.

Planting

  • Corn is picky about its soil. Work in aged manure or compost the fall before planting and let over winter in the soil.
  • Starting seeds indoors is not recommended.
  • Plant seeds outdoors two weeks after the last spring frost date.
  • Make sure soil temperature is above 60 degrees for successful germination. (Up to 65 for super sweet varieties.) In colder zones, the ground can be warmed by a black plastic cover if necessary. Plant seeds through holes.
  • Plant seeds 1 inch deep and 4 to 6 inches apart. Rows 30 to 36 inches apart.
  • For sufficient pollination, plan your plot right. Don’t plant two long rows, rather, plant corn blocks of at least four rows.
  • You may choose to fertilize at planting time, corn is meant to grow rapidly. If you are confident that the soil is adequate, this can be skipped.
  • Water well at planting time.

Care

  • When your plants are 3 to 4 inches tall, thin them so they are 8 to 12 inches apart.
  • Be careful not to damage the roots when weeding.
  • Soil must be well drained and able to keep consistent moisture.
  • In dry conditions, be sure to keep corn well watered due to its shallow roots. Water at a rate of 5 gallons per sq yard. Mulch helps reduce evaporation.

Harvest/Storage

  • Harvest when tassels begin to turn brown and cobs start to swell. Kernels should be full and milky.
  • Pull ears downward and twist to take off stalk.
  • Sweet corn varieties lose their sweetness soon after harvesting.
  • Prepare for eating or preserving immediately after picking.
  • Sweet corn freezes well, especially if removed from ears before freezing. Learn how to properly freeze corn.
  • Corn kernels can also be harvested for other purposes, like corn-filled therapy packs.

Recommended Varieties

There are three types of sweet corn: Normal, sugar enhanced and super sweet. Each one contains a different level of sucrose, changing the flavor and texture of the corn. Sweeter varieties will stay sweeter for longer after harvest.

  • ‘Iochief’ Midseason normal-sugar variety. Yellow.
  • ‘Silver Queen’ normal sugar-variety. Resistant to some bacterial diseases. White.
  • ‘Challenger Crisp n Sweet’ supersweet variety, resistant to some diseases, high yield. Yellow.
  • ‘Pristine’ sugar enhanced variety, good taste. White.