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How Sweet It Is · Zones 4–9
Growing Details
Zone-by-Zone Planting Calendar
Complete Growing Guide
Start by selecting a sunny location with well-draining soil that receives 6-8 hours of direct sunlight daily. How Sweet It Is performs best in fertile ground with a pH between 6.0-6.8. Work 2-3 inches of compost or aged manure into the planting area two weeks before sowing, as this supersweet variety demands rich soil to develop its signature sweetness.
Wait until soil temperature reaches a consistent 65°F before direct seeding—cold soil will cause poor germination or rotting seeds. Plant seeds 1-1.5 inches deep and 4-6 inches apart in blocks rather than single rows to ensure proper pollination. Space rows 30-36 inches apart to accommodate the 6-foot mature height. As a supersweet (sh2) variety, you must isolate How Sweet It Is from other corn types by at least 250 feet or stagger planting dates by 2-3 weeks to prevent cross-pollination that ruins the sweet flavor.
Side-dress with nitrogen-rich fertilizer when plants reach 12 inches tall and again when they're knee-high. Apply 1 tablespoon of 10-10-10 fertilizer per plant, working it into the soil 6 inches from the base. Maintain consistent moisture throughout the growing season—corn needs about 1 inch of water weekly, with critical periods being germination and tasseling.
Avoid the common mistake of planting too early when soil is still cool. Unlike standard sweet corn varieties, supersweet types like How Sweet It Is are more sensitive to cold conditions. Also resist the urge to remove suckers (side shoots)—they actually help support the main stalk and don't reduce ear production. Hill soil around the base when plants reach 3 feet tall to prevent wind damage, as the compact 6-foot height can still be vulnerable to strong storms in zones 6-7.
Harvesting
Harvest How Sweet It Is approximately 87-92 days from planting when silks turn brown and dry, and kernels are plump and milky. The most reliable test is puncturing a kernel with your thumbnail—it should release a sweet, milky juice rather than clear liquid (too early) or thick, pasty substance (overripe). Ears should feel full and firm from tip to base, with no gaps between kernel rows.
Harvest in early morning when temperatures are coolest to maximize sweetness retention. Twist ears downward while pulling away from the stalk, or cut the stem 1 inch below the ear with a sharp knife. Unlike standard sweet corn that loses sweetness within hours, How Sweet It Is maintains its sugar content for several days, but immediate harvesting after peak ripeness ensures the best eating quality. Check ears daily once silks brown, as the harvest window spans only 5-7 days before kernels become starchy.
Storage & Preservation
Store unhusked ears immediately in the refrigerator at 32-35°F to preserve maximum sweetness—How Sweet It Is retains its sugar content better than standard varieties but still benefits from prompt cooling. Keep husks on until ready to use, and consume within 5-7 days for peak flavor.
For long-term storage, blanch husked ears in boiling water for 4-6 minutes depending on size, then plunge into ice water before freezing. The supersweet kernels freeze exceptionally well, maintaining their tender texture for up to 12 months. You can also cut kernels from cobs and freeze in portion-sized containers. Pressure canning works well for this variety—process pints for 55 minutes at 10 pounds pressure. Avoid dehydrating as the high sugar content doesn't dry well and becomes chewy.
History & Origin
How Sweet It Is was developed in the 1990s as part of the supersweet corn revolution that began with the discovery of the shrunken-2 (sh2) gene mutation at the University of Illinois in the 1970s. This genetic trait allows corn to convert less sugar to starch, creating varieties with 2-3 times the sweetness of standard sweet corn.
The variety was specifically bred to combine the intense sweetness of supersweet genetics with compact plant architecture suitable for home gardens. Traditional supersweet varieties often grew 8-10 feet tall with poor ear fill, making them impractical for smaller spaces. Plant breeders focused on developing shorter plants while maintaining full-sized ears and the extended post-harvest sweetness that made supersweet corn popular with commercial growers.
The name reflects both the variety's exceptional sweetness and the satisfaction gardeners feel when growing their own premium corn. How Sweet It Is became commercially available in the early 2000s and quickly gained popularity among home gardeners who wanted restaurant-quality corn without dedicating excessive garden space to tall, sprawling plants.
Advantages
- +Maintains sweetness 3-5 days after harvest unlike standard sweet corn that turns starchy within hours
- +Compact 6-foot height fits in smaller gardens while producing full-sized 8-inch ears
- +Excellent tip fill with uniform kernel development reduces waste
- +Stewart's wilt resistance prevents bacterial disease common in humid climates
- +Exceptionally tender kernels require minimal cooking time
- +White kernels don't stain like yellow varieties when processing
- +Reliable ear production even in shorter growing seasons due to 87-day maturity
Considerations
- -Requires isolation from other corn types or sweetness is compromised by cross-pollination
- -More expensive seed costs compared to open-pollinated varieties
- -Sensitive to cold soil temperatures and won't germinate below 65°F
- -Susceptible to corn earworm damage near harvest time
- -Moderate difficulty level makes it challenging for beginning gardeners
Companion Plants
Plant Together
Bush Beans
Fix nitrogen in soil that corn can utilize, classic Three Sisters companion
Pole Beans
Climb corn stalks for support while fixing nitrogen to benefit corn
Winter Squash
Large leaves suppress weeds and retain soil moisture, completes Three Sisters guild
Marigolds
Repel corn earworm, aphids, and nematodes with strong scent
Nasturtiums
Act as trap crop for aphids and squash bugs, repel corn borers
Dill
Attracts beneficial insects that prey on corn pests like aphids
Sunflowers
Attract beneficial insects and birds that eat corn pests
Cucumbers
Benefit from corn's wind protection and shade during hot weather
Keep Apart
Black Walnut
Produces juglone which is toxic to corn and inhibits growth
Tomatoes
Both are heavy feeders competing for nutrients, attract similar pests like corn earworm
Fennel
Allelopathic properties inhibit corn germination and growth
Pests & Disease Resistance
Resistance
Resistant to Stewart's wilt, moderate resistance to rust diseases
Common Pests
Corn earworm, Japanese beetles, corn borer, aphids
Diseases
Northern corn leaf blight, gray leaf spot, crazy top