When to Plant Feverfew in Lethbridge, AB
Feverfew is a bushy perennial herb with small daisy-like flowers and aromatic leaves. It has been used traditionally for headache relief and is a cheerful garden plant.
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 Feverfew to ensure they mature before fall.
Lethbridge Soil Profile
Soil Type
Dark Brown Chernozem
Soil pH
6.0-7.0
Drainage
Well Drained
Plant 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 Feverfew
Plant Water Budget
Monthly Watering Guide for Feverfew
Feverfew 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 | Feverfew 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.
Feverfew 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.
Feverfew Planting Timeline — Lethbridge, AB
Feverfew Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 12 | May 12 – May 26 |
| Harvest | August 11 | Aug 11 – Oct 27 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
160 days in Lethbridge
Growing Tips for Feverfew in Lethbridge
Common pests for Feverfew 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. Feverfew needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors or direct sow on the soil surface. Deadhead regularly to prevent aggressive self-seeding. Divide clumps every 2-3 years to maintain vigor.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Feverfew in Other Locations
Frequently Asked Questions
When should I plant Feverfew in Lethbridge, AB?
Lethbridge is in Zone 5a with an average last frost of May 5. Plan your Feverfew 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.
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