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When to Plant Collard Greens in Hardin County, KY

Hardin County, Kentucky Zone 7a May

May to-do list for Hardin County, Kentucky

We've pulled the most time-sensitive tasks for Hardin County, Kentucky this May and put them front and centre. Tackle them in order.

Avg. last frost April 4
Avg. first frost November 1
Soil temp (4") 60°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs
  1. Start collard greens under lights

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. Harvest collard greens as they ripen

    If you can't use it all right away, check the food-preservation section of your planner.

Get ahead of June
  • First harvests: collard greens

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Collard greens are a heat-tolerant member of the cabbage family with large, sturdy leaves. They are a Southern staple and one of the most nutritious leafy greens.

Hardin County, Kentucky is in USDA Zone 7a. The average last spring frost is April 4 and the first fall frost is November 1, giving you a growing season of approximately 211 days.

At an elevation of 1,464 feet, Hardin County receives approximately 48.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Collard Greens during the growing season.

Hardin County, KY (Zone 7a) Long season
211 days
Last Spring Frost April 4
211 growing days
First Fall Frost November 1
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Hardin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (92 days to spare)
Start indoors: Feb 22 Transplant: Mar 29 🍅 Harvest: May 24 – Jul 26
Recommended (50%) ✓ Fits season (92 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 30 – Aug 1
Safe Start (90%) ✓ Fits season (86 days to spare)
Start indoors: Mar 18 Transplant: Apr 22 🍅 Harvest: Jun 17 – Aug 19

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 Hardin County

How your county's soil matches Collard Greens's growing requirements.

Soil pH

Your soil pH (5.7–6.8) overlaps with Collard Greens's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Collard Greens.

Organic Matter

Organic matter is moderate (2.9%). Annual compost additions will help Collard Greens.

How to Plant Collard Greens

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Collard Greens

4
successive plantings in your 211-day season

Sow every 6.3 weeks. Last sowing by Aug 18 to harvest before frost.

For a dedicated fall crop, sow by Aug 23.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Collard Greens

Collard Greens needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Collard Greens Needs Rainfall You Supplement Action
Jan 4.5" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.2" 0" ❄️ Dormant
Apr 3.5" 4.2" 0" ✅ Rainfall sufficient
May 3.5" 3.4" 0.1" 💧 Light watering
Jun 3.5" 4.2" 0" ✅ Rainfall sufficient
Jul 3.5" 5.6" 0" ✅ Rainfall sufficient
Aug 3.5" 5" 0" ✅ Rainfall sufficient
Sep 3.5" 3.5" 0" ✅ Rainfall sufficient
Oct 3.5" 2.8" 0.7" 💧 Light watering
Nov 3.5" 3.9" 0" ✅ Rainfall sufficient
Dec 3.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Hardin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Collard Greens 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.

Collard Greens needs ~991 GDD — county provides 3,217 GDD Excellent fit

Collard Greens Planting Timeline — Hardin County, KY

Collard Greens Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 – Mar 14
Transplant Outdoors April 4 Apr 4 – Apr 18
Direct Sow March 21 Mar 21 – Apr 11
Harvest May 30 May 30 – Aug 1
Fall Sowing August 23 Aug 23 – Sep 6

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
August Fall Sowing Harvest
September Fall Sowing
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

55–75 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

211 days in Hardin County

Growing Tips for Collard Greens in Hardin County

Direct sow Collard Greens outdoors after April 04 in Hardin County when soil has warmed and frost danger has passed.

Common pests for Collard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors or direct sow 4-6 weeks before last frost. Harvest lower leaves first, leaving the growing tip intact. Flavor improves after exposure to frost.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Collard Greens in Hardin County, KY?

Hardin County is in Zone 7a with an average last frost of April 4. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hardin County, KY?

Hardin County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 4 and first fall frost is November 1.

🌱

Your Hardin County Garden Planner — Free

A 24-page printable planner built for Hardin 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 Hardin 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.