When to Plant Watermelon in Sept-Iles, QC
Watermelon is a sprawling vine crop that produces sweet, juicy fruits in hot weather. Varieties range from personal-sized icebox types to 50-pound giants.
Sept-Iles, Quebec is in USDA Zone 4a. The average last spring frost is May 16 and the first fall frost is October 3, giving you a growing season of approximately 140 days.
At an elevation of 173 feet, Sept-Iles receives approximately 19.5 inches of rainfall annually with predominantly gray-brown podzol soil. Summer highs average 70°F, so choose short-season varieties of Watermelon to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Watermelon successfully. Mulch heavily to conserve soil moisture.
Sept-Iles Soil Profile
Soil Type
Gray-Brown Podzol
Soil pH
6.0-7.0
Drainage
Well Drained
How Much Watermelon to Grow
For a family of 4, plant approximately 4 watermelon plants in about 8 sq ft. In Sept-Iles's 140-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Monthly Watering Guide for Watermelon
Watermelon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Watermelon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.3" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Jun | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Jul | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Aug | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Sep | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Oct | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Sept-Iles). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Watermelon Planting Timeline — Sept-Iles, QC
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 4 | Apr 4 – Apr 18 |
| Transplant Outdoors | June 6 | Jun 6 – Jun 20 |
| Direct Sow | May 30 | May 30 – Jun 20 |
| Harvest | August 15 | Aug 15 – Oct 3 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 4a
📆 Growing Season
140 days in Sept-Iles
Growing Tips for Sept-Iles
Start seeds indoors 3-4 weeks early or direct sow after soil is warm. Plant on mounds with plenty of space. Check ripeness by looking for a yellow ground spot and dull thump when tapped.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Watermelon in Other Locations
Frequently Asked Questions
When should I plant Watermelon in Sept-Iles, QC?
Sept-Iles is in Zone 4a with an average last frost of May 16. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sept-Iles, QC?
Sept-Iles, Quebec is in USDA Hardiness Zone 4a. The average last spring frost is May 16 and first fall frost is October 3.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Sept-Iles gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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