Planting Timeline
Showing dates for Incredible in USDA Zone 7
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Incredible · Zones 3–9
Growing Details
Zone-by-Zone Planting Calendar
Complete Growing Guide
Start preparing your Incredible corn planting site in early spring by choosing a location that receives 6-8 hours of direct sunlight daily. Test your soil pH, aiming for 6.0-6.8, and work in 2-3 inches of well-aged compost or rotted manure to boost fertility. Corn is a heavy nitrogen feeder, so incorporating a balanced organic fertilizer (10-10-10) at 2 pounds per 100 square feet during soil preparation gives your plants the foundation they need.
Direct sow Incredible seeds once soil temperature consistently reaches 60°F, typically 2-3 weeks after your last frost date. Plant seeds 1 inch deep in cool climates, 2 inches deep in warmer areas, spacing them 6-8 inches apart in rows 30-36 inches wide. For better pollination and fuller ears, plant in blocks of at least 4 rows rather than single long rows. The wind-pollinated nature of corn means isolated plantings often result in poorly filled ears.
Fertilize when plants reach 8 inches tall with a nitrogen-rich fertilizer (blood meal or fish emulsion work excellently), then again when they're knee-high and just before tasseling. Apply fertilizer 6 inches from plant stems to avoid root burn. Maintain consistent soil moisture throughout the growing season, providing 1-1.5 inches weekly through deep, infrequent watering rather than shallow daily sprinklings.
Avoid planting too early when soil temperatures hover below 60°F – seeds often rot in cold, wet conditions. Many gardeners make the mistake of overcrowding plants; proper spacing prevents disease and ensures adequate nutrition for each stalk. For extended harvests, succession plant every 2 weeks through midsummer, though plantings after July may not mature before first frost in shorter season areas.
Incredible's strong stalks resist lodging better than many varieties, but hilling soil around the base when plants reach 12 inches tall provides extra stability. Watch for corn earworm and European corn borer damage, and consider beneficial nematodes as a biological control if these pests become problematic in your area.
Harvesting
Harvest Incredible corn when silks turn brown and dry, typically 85-90 days from planting, but don't rely on calendar dates alone. The most reliable test is pressing a kernel with your thumbnail – ripe kernels release milky juice, while overripe ones produce clear liquid or paste-like substance. Ears should feel plump and full when gently squeezed through the husk.
Perform the classic "twist test" by carefully peeling back a small portion of husk at the ear's tip to check kernel development. Kernels should be plump, well-formed, and filled to the ear's tip. Harvest in early morning when sugar content is highest, as kernels begin converting sugars to starch as temperatures rise throughout the day.
Remove ears by grasping the stalk firmly below the ear and twisting the ear downward while pulling. This clean break prevents damage to the plant's main stalk. Incredible's exceptional sugar retention means you have more harvest flexibility than standard varieties, but for peak sweetness, use ears within 2-3 days of picking. The variety's supersweet genetics maintain eating quality longer than traditional corn, making it forgiving for busy gardeners.
Storage & Preservation
Store fresh Incredible corn unhusked in the refrigerator immediately after harvest, where it maintains quality for 5-7 days – longer than most corn varieties due to its supersweet genetics. Keep husks on and place ears in perforated plastic bags to maintain moisture while allowing air circulation. For best flavor, avoid storing at room temperature, as even this variety will lose some sweetness over time.
For freezing, blanch husked ears in boiling water for 4-6 minutes depending on size, then plunge into ice water before cutting kernels from cob. Incredible freezes exceptionally well, maintaining its sweet flavor and tender texture for up to 12 months. Alternatively, freeze whole blanched ears wrapped individually in plastic wrap for grilling later.
Dehydrating kernels creates excellent additions to soups and stews – slice kernels from cobs and dry at 125°F until brittle. The variety's high sugar content makes it particularly suitable for corn relish and pickled corn recipes, where the sweetness balances vinegar and spices beautifully.
History & Origin
Incredible corn was developed through modern hybrid breeding programs focused on creating supersweet corn varieties that maintain their sugar content longer after harvest. This variety represents advances in corn breeding that began in the 1950s when geneticists discovered mutations that prevented the normal conversion of sugar to starch in corn kernels.
The development of supersweet varieties like Incredible revolutionized home corn growing by extending the "eating window" – the time between harvest and when corn becomes tough and starchy. Traditional corn varieties had to be rushed from garden to table, often harvested and cooked the same day for optimal eating quality.
Incredible's breeding specifically targeted disease resistance alongside sweetness, addressing common challenges home gardeners face with corn production. The variety's excellent resistance to northern corn leaf blight and rust reflects decades of breeding work to incorporate natural disease resistance genes into sweet corn lines. This breeding approach reduces the need for chemical treatments while ensuring reliable harvests across diverse growing conditions, making quality corn accessible to more home gardeners regardless of their local disease pressures.
Advantages
- +Maintains exceptional sweetness 3-5 days post-harvest, unlike standard varieties that lose sugar content within hours
- +Strong stalks with excellent lodging resistance handle winds up to 45 mph without falling over
- +Superior northern corn leaf blight resistance prevents the yellowing and death of lower leaves common in humid climates
- +Large, consistently filled ears average 8-9 inches with minimal tip gaps or missing kernels
- +Extended harvest window allows picking ears over 2-3 weeks from the same planting
- +Excellent germination rates even in cooler soil conditions down to 60°F
- +Kernels retain tender texture even when slightly overmature, forgiving harvest timing mistakes
Considerations
- -85-90 day maturity requires long growing season, limiting success in zones 3-4 without season extension
- -Higher seed cost than open-pollinated varieties, and seeds cannot be saved for replanting
- -Requires consistent, heavy fertilization throughout season, particularly nitrogen applications
- -Large ears and vigorous growth demand wider spacing, reducing plants per square foot
- -Supersweet genetics can result in poor germination if planted in cold, wet soil conditions
Companion Plants
Plant Together
Beans
Fix nitrogen in soil that corn can utilize, part of traditional Three Sisters planting
Squash
Large leaves provide ground cover and moisture retention, completes Three Sisters guild
Nasturtiums
Trap crop for cucumber beetles and squash bugs, deters corn earworm
Marigolds
Repel corn earworm, aphids, and nematodes with strong scent
Sunflowers
Attract beneficial insects and provide windbreak protection for corn
Dill
Attracts beneficial wasps that parasitize corn borers and other pests
Sweet Alyssum
Attracts hover flies and other beneficial insects that control aphids
Radishes
Break up compacted soil and may deter corn borers when interplanted
Keep Apart
Tomatoes
Both are heavy nitrogen feeders creating competition, tomato hornworms may spread to corn
Black Walnut Trees
Release juglone toxin that inhibits corn growth and development
Fennel
Allelopathic compounds inhibit corn germination and growth
Pests & Disease Resistance
Resistance
Excellent resistance to northern corn leaf blight, rust, and bacterial wilt
Common Pests
Corn earworm, European corn borer, birds, raccoons
Diseases
Common smut, gray leaf spot, southern rust