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When to Plant Leeks in Drumheller, AB

Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.

Drumheller, Alberta is in USDA Zone 5a. The average last spring frost is May 7 and the first fall frost is October 14, giving you a growing season of approximately 160 days.

At an elevation of 2,651 feet, Drumheller receives approximately 28.6 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 76°F, so choose short-season varieties of Leeks to ensure they mature before fall.

Drumheller, AB (Zone 5a) Moderate season
160 days
Last Spring Frost May 7
160 growing days
First Fall Frost October 14
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Drumheller Soil Profile

Soil Type

Dark Brown Chernozem

Soil pH

6.0-7.0

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (15 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 15 – Sep 30
Recommended (50%) ✓ Fits season (15 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 15 – Sep 30
Safe Start (90%) ✓ Fits season (15 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 15 – Sep 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.

How to Plant Leeks

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

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

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.8″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 70 gal / 100 sq ft

Monthly Watering Guide for Leeks

Leeks 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 Leeks Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 2.9" 0" ❄️ Dormant
May 3.5" 3" 0.5" 💧 Light watering
Jun 3.5" 3.5" 0" ✅ Rainfall sufficient
Jul 3.5" 2.8" 0.7" 💧 Light watering
Aug 3.5" 3.2" 0.3" 💧 Light watering
Sep 3.5" 2.5" 1" 💧 Light watering
Oct 3.5" 2.4" 1.1" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

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

Leeks 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.

Leeks needs ~840 GDD — county provides 1,120 GDD Excellent fit

Leeks Planting Timeline — Drumheller, AB

Leeks Planting Calendar

Activity When Date Range
Start Indoors April 2 Apr 2 – Apr 16
Transplant Outdoors May 7 May 7 – May 21
Direct Sow April 23 Apr 23 – May 14
Harvest August 6 Aug 6 – Oct 22
Fall Sowing August 5 Aug 5 – Aug 19

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

Month-by-Month Timeline

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

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

160 days in Drumheller

Growing Tips for Leeks in Drumheller

Your 160.0-day growing season in Drumheller is tight for Leeks (90.0-150.0 days to maturity). Start indoors and choose early-maturing varieties.

Common pests for Leeks in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Leeks in Drumheller, AB?

Drumheller is in Zone 5a with an average last frost of May 7. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.

What planting zone is Drumheller, AB?

Drumheller, Alberta is in USDA Hardiness Zone 5a. The average last spring frost is May 7 and first fall frost is October 14.

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Your Drumheller Garden Planner — Free

A 24-page printable planner built for Drumheller (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 Drumheller, AB. Local conditions may vary. Last updated: May 2026.

Sources & credits

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