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When to Plant Sweet Corn in Shelby County, TN

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.

Shelby County, Tennessee is in USDA Zone 7b. The average last spring frost is March 21 and the first fall frost is November 5, giving you a growing season of approximately 229 days.

At an elevation of 3,465 feet, Shelby County receives approximately 45.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Sweet Corn during the growing season.

Shelby County, TN (Zone 7b) Long season
229 days
Last Spring Frost March 21
229 growing days
First Fall Frost November 5

Shelby County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (127 days to spare)
Transplant: Mar 14 🍅 Harvest: May 16 – Jun 27
Recommended (50%) ✓ Fits season (124 days to spare)
Transplant: Mar 21 🍅 Harvest: May 23 – Jul 4
Safe Start (90%) ✓ Fits season (124 days to spare)
Transplant: Apr 10 🍅 Harvest: Jun 12 – Jul 24

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 Shelby County

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

Soil pH

Your soil pH (5.3โ€“7.0) overlaps with Sweet Corn's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Sweet Corn.

How to Plant Sweet Corn

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

Succession Planting Sweet Corn

4
successive plantings in your 229-day season

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

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.8″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,349 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€” 3.3" 0" โ„๏ธ Dormant
Feb โ€” 3.8" 0" โ„๏ธ Dormant
Mar 6.5" 4.2" 2.3" ๐Ÿ’ง Light watering
Apr 6.5" 2.9" 3.6" ๐Ÿšฟ Regular watering
May 6.5" 3.6" 2.9" ๐Ÿ’ง Light watering
Jun 6.5" 4.6" 1.9" ๐Ÿ’ง Light watering
Jul 6.5" 5.1" 1.4" ๐Ÿ’ง Light watering
Aug 6.5" 4.7" 1.8" ๐Ÿ’ง Light watering
Sep 6.5" 3" 3.5" ๐Ÿšฟ Regular watering
Oct 6.5" 3.3" 3.2" ๐Ÿ’ง Light watering
Nov 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Dec โ€” 3.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Shelby 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 ~1,256 GDD — county provides 3,835 GDD Excellent fit

Sweet Corn Planting Timeline โ€” Shelby County, TN

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow March 28 Mar 28 โ€“ Apr 18
Harvest May 30 May 30 โ€“ Jul 11

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.5"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

229 days in Shelby County

Growing Tips for Sweet Corn in Shelby County

Direct sow Sweet Corn outdoors after March 21 in Shelby 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.

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 Shelby County, TN?

Shelby County is in Zone 7b with an average last frost of March 21. Plan your Sweet Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Shelby County, TN?

Shelby County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is March 21 and first fall frost is November 5.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Shelby County gardeners in Zone 7b 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 Shelby County, TN. Local conditions may vary. Last updated: April 2026.