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When to Plant Corn in Martin County, NC

Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

Martin County, North Carolina is in USDA Zone 7b. The average last spring frost is March 26 and the first fall frost is November 12, giving you a growing season of approximately 231 days.

At an elevation of 565 feet, Martin County receives approximately 46.9 inches of rainfall annually with predominantly clay loam soil. Summer highs average 92ยฐF, providing good warmth for Corn during the growing season. Clay soil retains moisture well for Corn, but amend with compost to improve drainage and prevent root rot.

Martin County, NC (Zone 7b) Long season
231 days
Last Spring Frost March 26
231 growing days
First Fall Frost November 12

Martin County Soil Profile

Soil Type

Clay Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (112 days to spare)
Transplant: Mar 20 🍅 Harvest: May 22 – Jul 17
Recommended (50%) ✓ Fits season (112 days to spare)
Transplant: Mar 26 🍅 Harvest: May 28 – Jul 23
Safe Start (90%) ✓ Fits season (115 days to spare)
Transplant: Apr 9 🍅 Harvest: Jun 11 – Aug 6

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 Martin County

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

Soil pH

Your soil pH (5.5โ€“6.5) overlaps with Corn's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Corn.

How to Plant Corn

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

Succession Planting Corn

4
successive plantings in your 231-day season

Sow every 6.9 weeks. Last sowing by Aug 04 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,331 gal / 100 sq ft

Monthly Watering Guide for Corn

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 Corn Needs Rainfall You Supplement Action
Jan โ€” 4.1" 0" โ„๏ธ Dormant
Feb โ€” 3.7" 0" โ„๏ธ Dormant
Mar 6.5" 5" 1.5" ๐Ÿ’ง Light watering
Apr 6.5" 3.2" 3.3" ๐Ÿšฟ Regular watering
May 6.5" 3.8" 2.7" ๐Ÿ’ง Light watering
Jun 6.5" 4.1" 2.4" ๐Ÿ’ง Light watering
Jul 6.5" 4.3" 2.2" ๐Ÿ’ง Light watering
Aug 6.5" 5.1" 1.4" ๐Ÿ’ง Light watering
Sep 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Oct 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Nov 6.5" 3.3" 3.2" ๐Ÿ’ง Light watering
Dec โ€” 3.7" 0" โ„๏ธ Dormant

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

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.

Corn needs ~1,520 GDD — county provides 4,389 GDD Excellent fit

Corn Planting Timeline โ€” Martin County, NC

Corn Planting Calendar

Activity When Date Range
Direct Sow April 2 Apr 2 โ€“ Apr 23
Harvest June 4 Jun 4 โ€“ Jul 30

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Direct Sow
May โ€”
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€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

231 days in Martin County

Growing Tips for Corn in Martin County

Direct sow Corn outdoors after March 26 in Martin County when soil has warmed and frost danger has passed.

With Martin County's clay soil (29% clay), work in 3-4 inches of compost before planting Corn. Avoid tilling when soil is wet to prevent compaction.

Common pests for 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 rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in Martin County, NC?

Martin County is in Zone 7b with an average last frost of March 26. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Martin County, NC?

Martin County, North Carolina is in USDA Hardiness Zone 7b. The average last spring frost is March 26 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Martin 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 Martin County, NC. Local conditions may vary. Last updated: April 2026.