When to Plant Gaillardia (Blanket Flower) in Lethbridge, AB
Gaillardia (Gaillardia aristata), the native blanket flower of the American West, is one of the most floriferous and longest-blooming perennials available — producing cheerful, daisy-like flowers in fiery red, orange, and yellow combinations from early summer through hard frost in most climates. Named for the way its spreading colonies mimic the patterned blankets of Indigenous American weavers, gaillardia thrives in the exact conditions that challenge other perennials: poor, dry, gravelly soil in full sun. An outstanding pollinator plant, attracting bees, butterflies, and finches that feed on its seed heads. Somewhat short-lived (3–5 years) but self-seeds freely to sustain garden colonies.
Lethbridge, Alberta is in USDA Zone 5a. The average last spring frost is May 5 and the first fall frost is October 12, giving you a growing season of approximately 160 days.
At an elevation of 2,985 feet, Lethbridge receives approximately 23.7 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 74°F, so choose short-season varieties of Gaillardia (Blanket Flower) to ensure they mature before fall.
Lethbridge Soil Profile
Soil Type
Dark Brown Chernozem
Soil pH
6.0-7.0
Drainage
Well Drained
Gaillardia (Blanket Flower) Planting Risk Windows
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 Gaillardia (Blanket Flower)
Gaillardia (Blanket Flower) Water Budget
Monthly Watering Guide for Gaillardia (Blanket Flower)
Gaillardia (Blanket Flower) 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 | Gaillardia (Blanket Flower) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.9" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Oct | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Lethbridge). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Gaillardia (Blanket Flower) 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.
Gaillardia (Blanket Flower) Planting Timeline — Lethbridge, AB
Gaillardia (Blanket Flower) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 10 | Mar 10 – Mar 24 |
| Transplant Outdoors | May 19 | May 19 – Jun 2 |
| Direct Sow | May 19 | May 19 – Jun 9 |
| Bloom | July 28 | Jul 28 – Nov 17 |
Plant 0.1" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
160 days in Lethbridge
Growing Tips for Gaillardia (Blanket Flower) in Lethbridge
Common pests for Gaillardia (Blanket Flower) in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
Lethbridge receives only 24" of rain annually. Gaillardia (Blanket Flower) needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6–8 weeks before last frost or direct-sow after last frost. Seeds need light to germinate — press onto soil surface without covering, or cover very lightly (1/8 inch). Transplant after last frost when soil has warmed. Lean, well-drained soil is essential — rich or wet soil causes sprawl and root rot. Deadhead spent blooms to prolong the season, but leave some heads for self-seeding to renew the planting. Divide every 2–3 years in spring to maintain vigor. Drought-tolerant once established; overwatering is more damaging than underwatering. Year 2+ plants deliver the fullest multi-season bloom.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Gaillardia (Blanket Flower) in Other Locations
Frequently Asked Questions
When should I plant Gaillardia (Blanket Flower) in Lethbridge, AB?
Lethbridge is in Zone 5a with an average last frost of May 5. Plan your Gaillardia (Blanket Flower) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lethbridge, AB?
Lethbridge, Alberta is in USDA Hardiness Zone 5a. The average last spring frost is May 5 and first fall frost is October 12.
Your Lethbridge Garden Planner — Free
A 22-page printable planner built for Lethbridge (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.