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When to Plant Collard Greens in Grant County, KS

Grant County, Kansas Zone 6b May

Your May gardening checklist

Welcome to May in Zone 6b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 21
Avg. first frost October 17
Soil temp (4") 62°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs
  1. Fire up the seed-starting tray: collard greens

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

June prep starts now
  • 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.

Grant County, Kansas is in USDA Zone 6b. The average last spring frost is April 21 and the first fall frost is October 17, giving you a growing season of approximately 179 days.

At an elevation of 1,096 feet, Grant County receives approximately 25.2 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Collard Greens during the growing season.

Grant County, KS (Zone 6b) Moderate season
179 days
Last Spring Frost April 21
179 growing days
First Fall Frost October 17

Grant County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (60 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: Jun 11 – Aug 13
Recommended (50%) ✓ Fits season (60 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jun 16 – Aug 18
Safe Start (90%) ✓ Fits season (62 days to spare)
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Jun 29 – Aug 31

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 Grant County

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

Soil pH

Your soil pH (6.4–7.7) is more alkaline than Collard Greens prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.1%) — Collard Greens will thrive.

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

3
successive plantings in your 179-day season

Sow every 6.3 weeks. Last sowing by Aug 03 to harvest before frost.

For a dedicated fall crop, sow by Aug 08.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.6″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 399 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 1.8" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 3.5" 3" 0.5" 💧 Light watering
May 3.5" 2.8" 0.7" 💧 Light watering
Jun 3.5" 1.9" 1.6" 💧 Light watering
Jul 3.5" 2" 1.5" 💧 Light watering
Aug 3.5" 2.7" 0.8" 💧 Light watering
Sep 3.5" 2.4" 1.1" 💧 Light watering
Oct 3.5" 2.1" 1.4" 💧 Light watering
Nov 1.6" 0" ❄️ Dormant
Dec 1.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Grant 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 ~894 GDD — county provides 2,461 GDD Excellent fit

Collard Greens Planting Timeline — Grant County, KS

Collard Greens Planting Calendar

Activity When Date Range
Start Indoors March 17 Mar 17 – Mar 31
Transplant Outdoors April 21 Apr 21 – May 5
Direct Sow April 7 Apr 7 – Apr 28
Harvest June 16 Jun 16 – Aug 18
Fall Sowing August 8 Aug 8 – Aug 22

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

55–75 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6b

📆 Growing Season

179 days in Grant County

Growing Tips for Collard Greens in Grant County

Direct sow Collard Greens outdoors after April 21 in Grant 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 Grant County, KS?

Grant County is in Zone 6b with an average last frost of April 21. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Grant County, KS?

Grant County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 21 and first fall frost is October 17.

🌱

Your Grant County Garden Planner — Free

A 24-page printable planner built for Grant County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Grant County, KS. 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.