When to Plant Lavender in Trois-Rivieres, QC
Lavender (Lavandula angustifolia) is a fragrant Mediterranean sub-shrub prized for its silver-gray foliage and intensely aromatic purple flower spikes. A classic companion for roses and an unmatched pollinator magnet, lavender thrives in the exact conditions that challenge many plants: poor, rocky, alkaline soil with excellent drainage and full sun. English lavender is the most cold-hardy species, reliably perennial in Zones 5–9. Fresh or dried flowers are widely used in sachets, essential oils, culinary applications, and dried arrangements.
Trois-Rivieres, Quebec is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 8, giving you a growing season of approximately 167 days.
At an elevation of 49 feet, Trois-Rivieres receives approximately 23.5 inches of rainfall annually with predominantly gray-brown podzol soil. Summer highs average 75°F, so choose short-season varieties of Lavender to ensure they mature before fall.
Trois-Rivieres Soil Profile
Soil Type
Gray-Brown Podzol
Soil pH
6.0-7.0
Drainage
Well Drained
Lavender Planting Timeline — Trois-Rivieres, QC
Lavender Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 13 | Feb 13 – Feb 27 |
| Transplant Outdoors | May 15 | May 15 – May 29 |
| Bloom | July 24 | Jul 24 – Sep 11 |
Plant 0.5" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
167 days in Trois-Rivieres
Growing Tips for Trois-Rivieres
The single most important requirement for lavender success is excellent drainage — it will rot in heavy clay or wet winter soils before cold alone kills it. Amend with coarse sand or fine gravel if needed; raised beds work well in Zones 5–6. Start from rooted cuttings or transplants rather than seed for named cultivars. Transplant after last frost when soil is reliably warm (55°F+). Avoid rich or overly moist soils. Prune lightly after each flush of bloom, but never cut into old wood below the green growth zone — it will not regenerate from leafless woody stems. In Zones 5–6, mulch lightly with gravel (not bark/organic material which traps moisture) around the crown for winter protection. Year 2+ plants develop into full, mature shrubs with the most prolific bloom.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lavender in Other Locations
Frequently Asked Questions
When should I plant Lavender in Trois-Rivieres, QC?
Trois-Rivieres is in Zone 5b with an average last frost of April 24. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.
What planting zone is Trois-Rivieres, QC?
Trois-Rivieres, Quebec is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 8.
Your Trois-Rivieres Garden Planner — Free
A 22-page printable planner built for Trois-Rivieres (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.