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When to Plant Corn in Calgary, AB

Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

Calgary, 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 3,428 feet, Calgary receives approximately 26.9 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 75ยฐF, so choose short-season varieties of Corn to ensure they mature before fall.

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

Calgary Soil Profile

Soil Type

Dark Brown Chernozem

Soil pH

6.0-7.0

Drainage

Well Drained

How Much Corn to Grow

1-2 ears
Average yield per plant
15
Plants per person
30 sq ft
Space per person

For a family of 4, plant approximately 60 corn plants in about 120 sq ft. In Calgary's 160-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Corn

Corn needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Corn Needs Rainfall You Supplement Action
Jan โ€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 1.2" 0" โ„๏ธ Dormant
Mar โ€” 2.1" 0" โ„๏ธ Dormant
Apr โ€” 2.5" 0" โ„๏ธ Dormant
May 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Jun 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Jul 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Aug 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Sep 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
Oct 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Nov โ€” 1.9" 0" โ„๏ธ Dormant
Dec โ€” 1.4" 0" โ„๏ธ Dormant

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

Corn Planting Timeline โ€” Calgary, AB

Corn Planting Calendar

Activity When Date Range
Direct Sow May 14 May 14 โ€“ Jun 4
Harvest July 16 Jul 16 โ€“ Sep 10

Plant 1" deep ยท 12" apart ยท Rows 36" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Direct Sow
June Direct Sow
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

60โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

160 days in Calgary

Growing Tips for Calgary

Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in Calgary, AB?

Calgary is in Zone 5a with an average last frost of May 7. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Calgary, AB?

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

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Calgary gardeners in Zone 5a 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 Calgary, AB. Local conditions may vary. Last updated: April 2026.