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When to Plant Yarrow in Red Deer, AB

Yarrow is a drought-tolerant perennial herb with feathery foliage and flat-topped flower clusters in white, yellow, pink, or red. It attracts beneficial insects and is used in herbal medicine.

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 Yarrow to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Yarrow 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 (29 days to spare)
Transplant: Apr 22 🍅 Harvest: Jul 22 – Sep 16
Recommended (50%) ✓ Fits season (29 days to spare)
Transplant: Apr 22 🍅 Harvest: Jul 22 – Sep 16
Safe Start (90%) ✓ Fits season (29 days to spare)
Transplant: Apr 22 🍅 Harvest: Jul 22 – Sep 16

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 Yarrow

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Plant Water Budget

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

Monthly Watering Guide for Yarrow

Yarrow needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Yarrow 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 2.2" 2.2" 0" โœ… Rainfall sufficient
Jun 2.2" 2.3" 0" โœ… Rainfall sufficient
Jul 2.2" 1.9" 0.3" ๐Ÿ’ง Light watering
Aug 2.2" 1.7" 0.5" ๐Ÿ’ง Light watering
Sep 2.2" 1.6" 0.6" ๐Ÿ’ง Light watering
Oct 2.2" 1.4" 0.8" ๐Ÿ’ง Light 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.

Yarrow 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.

Yarrow needs ~656 GDD — county provides 918 GDD Excellent fit

Yarrow Planting Timeline โ€” Red Deer, AB

Yarrow Planting Calendar

Activity When Date Range
Transplant Outdoors May 18 May 18 โ€“ Jun 1
Harvest August 17 Aug 17 โ€“ Oct 12

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

147 days in Red Deer

Growing Tips for Yarrow in Red Deer

Common pests for Yarrow in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Red Deer receives only 18" of rain annually. Yarrow needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow or start from divisions. Yarrow thrives in poor soil and is very drought-tolerant. Deadhead to encourage reblooming. Divide clumps every 3 years.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Yarrow in Red Deer, AB?

Red Deer is in Zone 4b with an average last frost of May 11. Plan your Yarrow 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.

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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.