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When to Plant Corn in Martin County, KY

Martin County, Kentucky Zone 7a May

May in Martin County, Kentucky — your action list

Each item below is timed to Martin County, Kentucky's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 16
Avg. first frost October 27
Soil temp (4") 64°F
Watering Low
Pest pressure Low
Daylight 14 hrs
June prep starts now
  • First harvests: corn

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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, Kentucky is in USDA Zone 7a. The average last spring frost is April 16 and the first fall frost is October 27, giving you a growing season of approximately 194 days.

At an elevation of 1,188 feet, Martin County receives approximately 51.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Corn during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Corn root diseases.

Martin County, KY (Zone 7a) Moderate season
194 days
Last Spring Frost April 16
194 growing days
First Fall Frost October 27
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Martin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (75 days to spare)
Transplant: Apr 10 🍅 Harvest: Jun 12 – Aug 7
Recommended (50%) ✓ Fits season (75 days to spare)
Transplant: Apr 16 🍅 Harvest: Jun 18 – Aug 13
Safe Start (90%) ✓ Fits season (72 days to spare)
Transplant: May 3 🍅 Harvest: Jul 5 – 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 Martin County

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

Soil pH

Your soil pH (5.7–6.9) overlaps with Corn's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Martin County is excellent for Corn — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Corn.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Corn.

How to Plant Corn

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

Succession Planting Corn

3
successive plantings in your 194-day season

Sow every 6.9 weeks. Last sowing by Jul 19 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 4.7" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 5.4" 0" ❄️ Dormant
Apr 6.5" 4.3" 2.2" 💧 Light watering
May 6.5" 4.2" 2.3" 💧 Light watering
Jun 6.5" 4.3" 2.2" 💧 Light watering
Jul 6.5" 4.5" 2" 💧 Light watering
Aug 6.5" 4.1" 2.4" 💧 Light watering
Sep 6.5" 4" 2.5" 💧 Light watering
Oct 6.5" 3.6" 2.9" 💧 Light watering
Nov 4.2" 0" ❄️ Dormant
Dec 3.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Martin County). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~1,220 GDD — county provides 2,958 GDD Excellent fit

Corn Planting Timeline — Martin County, KY

Corn Planting Calendar

Activity When Date Range
Direct Sow April 23 Apr 23 – May 14
Harvest June 25 Jun 25 – Aug 20

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Direct Sow
May Direct Sow
June Harvest
July Harvest
August Harvest
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–100 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

194 days in Martin County

Growing Tips for Corn in Martin County

Direct sow Corn outdoors after April 16 in Martin County when soil has warmed and frost danger has passed.

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, KY?

Martin County is in Zone 7a with an average last frost of April 16. Plan your Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Martin County, KY?

Martin County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 16 and first fall frost is October 27.

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Your Martin County Garden Planner — Free

A 24-page printable planner built for Martin County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.