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When to Plant Kale in Red Deer, AB

Kale is an exceptionally hardy, nutrient-dense green available in curly, lacinato, and Russian varieties. It tolerates heavy frost and often tastes sweeter after cold exposure.

Red Deer, Alberta is in USDA Zone 4b. The average last spring frost is May 11 and the first fall frost is October 5, giving you a growing season of approximately 147 days.

At an elevation of 2,969 feet, Red Deer receives approximately 17.9 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 75ยฐF, so choose short-season varieties of Kale to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Kale successfully. Mulch heavily to conserve soil moisture.

Red Deer, AB (Zone 4b) Short season
147 days
Last Spring Frost May 11
147 growing days
First Fall Frost October 5

Red Deer 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 (71 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: Jun 10 – Aug 5
Recommended (50%) ✓ Fits season (71 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: Jun 10 – Aug 5
Safe Start (90%) ✓ Fits season (71 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: Jun 10 – Aug 5

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 Kale

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

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

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.5″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 378 gal / 100 sq ft

Monthly Watering Guide for Kale

Kale 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 Kale Needs Rainfall You Supplement Action
Jan โ€” 0.7" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 1.1" 0" โ„๏ธ Dormant
Apr โ€” 1.7" 0" โ„๏ธ Dormant
May 3.5" 2.2" 1.3" ๐Ÿ’ง Light watering
Jun 3.5" 2.3" 1.2" ๐Ÿ’ง Light watering
Jul 3.5" 1.9" 1.6" ๐Ÿ’ง Light watering
Aug 3.5" 1.7" 1.8" ๐Ÿšฟ Regular watering
Sep 3.5" 1.6" 1.9" ๐Ÿšฟ Regular watering
Oct 3.5" 1.4" 2.1" ๐Ÿšฟ Regular watering
Nov โ€” 1.4" 0" โ„๏ธ Dormant
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Red Deer). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Kale 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" โ€” every day above 50ยฐF 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.

Kale needs ~375 GDD — county provides 918 GDD Excellent fit

Kale Planting Timeline โ€” Red Deer, AB

Kale Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 โ€“ Apr 13
Transplant Outdoors May 11 May 11 โ€“ May 25
Direct Sow May 4 May 4 โ€“ May 25
Harvest July 6 Jul 6 โ€“ Aug 31
Fall Sowing July 13 Jul 13 โ€“ Jul 27

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

147 days in Red Deer

Growing Tips for Kale in Red Deer

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

General growing tips

Direct sow or transplant in early spring or late summer. Harvest outer leaves first to keep plants productive. Kale overwinters in many climates and can provide greens all year.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Kale Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Allow 2nd year flower stalks to dry. Harvest pods when tan.
Storage Store airtight; viable 5 years at 35ยฐF, under 50% humidity.

Isolate 1/2 mile from other brassicas (broccoli, cabbage, etc.) โ€” they all cross.

Frequently Asked Questions

When should I plant Kale in Red Deer, AB?

Red Deer is in Zone 4b with an average last frost of May 11. Plan your Kale planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Red Deer, AB?

Red Deer, Alberta is in USDA Hardiness Zone 4b. The average last spring frost is May 11 and first fall frost is October 5.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Red Deer gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Red Deer, AB. Local conditions may vary. Last updated: April 2026.