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When to Plant Collard Greens in Griggs County, ND

Griggs County, North Dakota Zone 4a May

May in the garden — Griggs County, North Dakota

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

Avg. last frost May 11
Avg. first frost September 30
Soil temp (4") 53°F
Watering Moderate
Pest pressure Low
Daylight 14.9 hrs
  1. Move collard greens from tray to bed

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

  2. Put collard greens seeds straight in the ground

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

June will be here before you know it — start on
  • Starting indoors: 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.

Griggs County, North Dakota is in USDA Zone 4a. The average last spring frost is May 11 and the first fall frost is September 30, giving you a growing season of approximately 142 days.

At an elevation of 660 feet, Griggs County receives approximately 21.4 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Collard Greens to ensure they mature before fall.

Griggs County, ND (Zone 4a) Short season
142 days
Last Spring Frost May 11
142 growing days
First Fall Frost September 30
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Griggs County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (25 days to spare)
Start indoors: Mar 21 Transplant: May 2 🍅 Harvest: Jun 27 – Aug 29
Recommended (50%) ✓ Fits season (23 days to spare)
Start indoors: Mar 30 Transplant: May 11 🍅 Harvest: Jul 6 – Sep 7
Safe Start (90%) ✓ Fits season (26 days to spare)
Start indoors: Apr 10 Transplant: May 22 🍅 Harvest: Jul 17 – Sep 18

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 Griggs County

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

Soil pH

Your soil pH (6.7–7.8) 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 Griggs County is excellent for Collard Greens — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.8%). Annual compost additions will help Collard Greens.

How to Plant Collard Greens

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Collard Greens

2
successive plantings in your 142-day season

Sow every 6.3 weeks. Last sowing by Jul 17 to harvest before frost.

For a dedicated fall crop, sow by Jul 08.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.6″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 253 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 0.6" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 2.2" 0" ❄️ Dormant
May 3.5" 3" 0.5" 💧 Light watering
Jun 3.5" 3.5" 0" ✅ Rainfall sufficient
Jul 3.5" 2.7" 0.8" 💧 Light watering
Aug 3.5" 2.4" 1.1" 💧 Light watering
Sep 3.5" 2" 1.5" 💧 Light watering
Oct 1.4" 0" ❄️ Dormant
Nov 0.7" 0" ❄️ Dormant
Dec 0.6" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Griggs 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 ~699 GDD — county provides 1,526 GDD Excellent fit

Collard Greens Planting Timeline — Griggs County, ND

Collard Greens Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Harvest July 6 Jul 6 – Sep 7
Fall Sowing July 8 Jul 8 – Jul 22

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June
July Fall Sowing Harvest
August Harvest
September Harvest
October
November
December
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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 4a

📆 Growing Season

142 days in Griggs County

Growing Tips for Collard Greens in Griggs County

Direct sow Collard Greens outdoors after May 11 in Griggs 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 Griggs County, ND?

Griggs County is in Zone 4a with an average last frost of May 11. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Griggs County, ND?

Griggs County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 11 and first fall frost is September 30.

🌱

Your Griggs County Garden Planner — Free

A 24-page printable planner built for Griggs County (Zone 4a). 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 Griggs County, ND. 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.