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When to Plant Sweet Corn in Valley County, NE

Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.

Valley County, Nebraska is in USDA Zone 4b. The average last spring frost is May 9 and the first fall frost is October 5, giving you a growing season of approximately 149 days.

At an elevation of 982 feet, Valley County receives approximately 21.7 inches of rainfall annually with predominantly loam soil. Summer highs average 82ยฐF, so choose short-season varieties of Sweet Corn to ensure they mature before fall.

Valley County, NE (Zone 4b) Short season
149 days
Last Spring Frost May 9
149 growing days
First Fall Frost October 5

Valley County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (48 days to spare)
Transplant: Apr 28 🍅 Harvest: Jun 30 – Aug 11
Recommended (50%) ✓ Fits season (44 days to spare)
Transplant: May 9 🍅 Harvest: Jul 11 – Aug 22
Safe Start (90%) ✓ Fits season (45 days to spare)
Transplant: May 17 🍅 Harvest: Jul 19 – Aug 30

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Valley County

How your county's soil matches Sweet Corn's growing requirements.

Soil pH

Your soil pH (6.7โ€“7.8) is more alkaline than Sweet Corn prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Valley County is excellent for Sweet Corn โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Sweet Corn.

Organic Matter

Organic matter is excellent (4.1%) โ€” Sweet Corn will thrive.

How to Plant Sweet Corn

1"
Planting Depth
12"
Between Plants
36"
Between Rows

Succession Planting Sweet Corn

2
successive plantings in your 149-day season

Sow every 6.9 weeks. Last sowing by Jul 07 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.6″/week
You supply
1.3″/week
Watering frequency 2-3 times/week
Season total 1,775 gal / 100 sq ft

Monthly Watering Guide for Sweet Corn

Sweet Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Sweet Corn Needs Rainfall You Supplement Action
Jan โ€” 0.6" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 1.5" 0" โ„๏ธ Dormant
Apr โ€” 1.9" 0" โ„๏ธ Dormant
May 6.5" 3.6" 2.9" ๐Ÿ’ง Light watering
Jun 6.5" 3.8" 2.7" ๐Ÿ’ง Light watering
Jul 6.5" 2.6" 3.9" ๐Ÿšฟ Regular watering
Aug 6.5" 2.2" 4.3" ๐Ÿšฟ Regular watering
Sep 6.5" 2.1" 4.4" ๐Ÿšฟ Regular watering
Oct 6.5" 1.2" 5.3" ๐Ÿšฟ Regular watering
Nov โ€” 0.8" 0" โ„๏ธ Dormant
Dec โ€” 0.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Valley County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sweet Corn Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Sweet Corn needs ~862 GDD — county provides 1,713 GDD Excellent fit

Sweet Corn Planting Timeline โ€” Valley County, NE

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow May 23 May 23 โ€“ Jun 13
Harvest July 25 Jul 25 โ€“ Sep 5

Plant 1" deep ยท 12" apart ยท Rows 36" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Direct Sow
June Direct Sow
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.5"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

149 days in Valley County

Growing Tips for Sweet Corn in Valley County

Direct sow Sweet Corn outdoors after May 09 in Valley County when soil has warmed and frost danger has passed.

Common pests for Sweet Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.

Valley County receives only 22" of rain annually. Sweet Corn needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant in blocks of at least 4 rows for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Corn in Valley County, NE?

Valley County is in Zone 4b with an average last frost of May 9. Plan your Sweet Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Valley County, NE?

Valley County, Nebraska is in USDA Hardiness Zone 4b. The average last spring frost is May 9 and first fall frost is October 5.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Valley County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Valley County, NE. Local conditions may vary. Last updated: April 2026.