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When to Plant Sunflower in Hanover, MB

Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.

Hanover, Manitoba is in USDA Zone 4b. The average last spring frost is May 8 and the first fall frost is October 2, giving you a growing season of approximately 147 days.

At an elevation of 813 feet, Hanover receives approximately 13.5 inches of rainfall annually with predominantly black chernozem soil. Summer highs average 70ยฐF, so choose short-season varieties of Sunflower to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Sunflower successfully. Mulch heavily to conserve soil moisture.

Hanover, MB (Zone 4b) Short season
147 days
Last Spring Frost May 8
147 growing days
First Fall Frost October 2

Hanover Soil Profile

Soil Type

Black Chernozem

Soil pH

6.0-7.0

Drainage

Well Drained

Monthly Watering Guide for Sunflower

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

Month Sunflower Needs Rainfall You Supplement Action
Jan โ€” 0.5" 0" โ„๏ธ Dormant
Feb โ€” 0.6" 0" โ„๏ธ Dormant
Mar โ€” 0.8" 0" โ„๏ธ Dormant
Apr โ€” 1.4" 0" โ„๏ธ Dormant
May 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Jun 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Jul 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Aug 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Sep 4.3" 1.3" 3" ๐Ÿšฟ Regular watering
Oct 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 0.8" 0" โ„๏ธ Dormant

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

Sunflower Planting Timeline โ€” Hanover, MB

Sunflower Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors May 29 May 29 โ€“ Jun 12
Direct Sow May 22 May 22 โ€“ Jun 12
Harvest August 7 Aug 7 โ€“ Sep 25

Plant 1" deep ยท 18" apart ยท Rows 30" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Low โ€” drought tolerant

๐Ÿ“… Days to Maturity

70โ€“100 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 Hanover

Growing Tips for Hanover

Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Hanover, MB?

Hanover is in Zone 4b with an average last frost of May 8. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hanover, MB?

Hanover, Manitoba is in USDA Hardiness Zone 4b. The average last spring frost is May 8 and first fall frost is October 2.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Hanover 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 Hanover, MB. Local conditions may vary. Last updated: April 2026.