Icon XR (F1) Corn Seed

Scientific name

Zea mays

Isolation

Super sweet (sh2) corn must not cross with other sweet corn or field corn, or the kernels of both turn starchy and tough. Plant sh2 varieties at least 300 feet from other types. Where you cannot get that distance, separate plantings in time instead, so they shed pollen at least two weeks apart, and keep a gap of at least 25 feet between them.

Soil temperature

Super sweet seed is small and sensitive to cold. Wait until the soil is at least 55–60°F (13–16°C) for treated seed, and at least 65°F (18°C) for untreated or organic seed.

Sowing

Sow 3/4–1" deep with seeds about 6–7" apart, or drop 2 seeds every 9" and thin to the stronger plant, in rows 30–36" apart. Sow a little more thickly with untreated seed.

Pollination

Corn is wind-pollinated, so plant blocks of at least four rows side by side rather than one long row. Single rows give poorly filled ears with missing kernels.

Succession planting

Keep planting into early summer, or sow several varieties of different maturity on the same day, to spread out the harvest.

Insect pests

Ask your local Extension office for current integrated pest management advice. Plowing in or composting stalks promptly after harvest reduces pests in next year’s crop.

Harvest

Note the date when about half the plants show silks; ears are usually ready 18–24 days later, sooner in hot weather. Pick when the silks have dried and browned and the kernels are plump and give a milky juice when pressed.

Days to maturity

Weather and planting date shift maturity a great deal, so use the figure to compare varieties rather than to predict an exact picking day.

Seeding rate

At 2 seeds per foot in rows 36" apart: about 1,000 seeds per 500 ft. and roughly 30,000 seeds per acre.

Packet

150 seeds.

Seeds per lb.

About 2,300 on average.