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When to Plant Collard Greens in Anchorage Municipality, AK

Anchorage Municipality, Alaska Zone 5a May

Top priorities for Anchorage Municipality, Alaska gardeners in May

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Anchorage Municipality, Alaska.

Avg. last frost May 15
Avg. first frost September 19
Soil temp (4") 46°F
Watering Critical
Pest pressure Low
Daylight 17.1 hrs
  1. Harden off and plant collard greens

    Your last frost (May 15) has passed. These warm-season crops can handle outdoor soil now.

  2. Scatter collard greens into prepared beds

    Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.

Get ahead of June
  • 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.

Anchorage Municipality, Alaska is in USDA Zone 5a. The average last spring frost is May 15 and the first fall frost is September 19, giving you a growing season of approximately 127 days.

At an elevation of 2,537 feet, Anchorage Municipality receives approximately 20.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 71°F, so choose short-season varieties of Collard Greens to ensure they mature before fall.

Anchorage Municipality, AK (Zone 5a) Short season
127 days
Last Spring Frost May 15
127 growing days
First Fall Frost September 19

Anchorage Municipality Soil Profile

Soil Type

Silt Loam

Soil pH

4.9-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (13 days to spare)
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Jun 29 – Aug 31
Recommended (50%) ✓ Fits season (8 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jul 10 – Sep 11
Safe Start (90%) ✓ Fits season (1 days to spare)
Start indoors: Apr 28 Transplant: Jun 2 🍅 Harvest: Jul 28 – Sep 29

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 Anchorage Municipality

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

Soil pH

Your soil pH (4.9–6.5) is more acidic than Collard Greens prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Anchorage Municipality 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 excellent (5.2%) — 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

2
successive plantings in your 127-day season

Sow every 6.3 weeks. Last sowing by Jul 06 to harvest before frost.

For a dedicated fall crop, sow by Jul 11.

Plant Water Budget

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

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" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 0.8" 0" ❄️ Dormant
Apr 0.6" 0" ❄️ Dormant
May 3.5" 0.9" 2.6" 🚿 Regular watering
Jun 3.5" 1.5" 2" 🚿 Regular watering
Jul 3.5" 2.6" 0.9" 💧 Light watering
Aug 3.5" 3.3" 0.2" 💧 Light watering
Sep 3.5" 3.2" 0.3" 💧 Light watering
Oct 2.4" 0" ❄️ Dormant
Nov 1.7" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Anchorage Municipality). 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 ~211 GDD — county provides 412 GDD Excellent fit

Collard Greens Planting Timeline — Anchorage Municipality, AK

Collard Greens Planting Calendar

Activity When Date Range
Start Indoors April 10 Apr 10 – Apr 24
Transplant Outdoors May 15 May 15 – May 29
Direct Sow May 1 May 1 – May 22
Harvest July 10 Jul 10 – Sep 11
Fall Sowing July 11 Jul 11 – Jul 25

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

Month-by-Month Timeline

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

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: too_acidic

🗺️ USDA Zone

Zone 5a

📆 Growing Season

127 days in Anchorage Municipality

Growing Tips for Collard Greens in Anchorage Municipality

Direct sow Collard Greens outdoors after May 15 in Anchorage Municipality 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 Anchorage Municipality, AK?

Anchorage Municipality is in Zone 5a with an average last frost of May 15. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Anchorage Municipality, AK?

Anchorage Municipality, Alaska is in USDA Hardiness Zone 5a. The average last spring frost is May 15 and first fall frost is September 19.

🌱

Your Anchorage Municipality Garden Planner — Free

A 24-page printable planner built for Anchorage Municipality (Zone 5a). 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 Anchorage Municipality, AK. 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.