When to Plant Onion in Rolette County, ND
Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.
Rolette County, North Dakota is in USDA Zone 3b. The average last spring frost is May 17 and the first fall frost is September 22, giving you a growing season of approximately 128 days.
At an elevation of 998 feet, Rolette County receives approximately 31.8 inches of rainfall annually with predominantly loam soil. Summer highs average 78°F, so choose short-season varieties of Onion to ensure they mature before fall.
Rolette County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
Drainage
Well Drained
Monthly Watering Guide for Onion
Onion needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Onion Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | — | 3.5" | 0" | ❄️ Dormant |
| May | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Sep | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Oct | — | 2.1" | 0" | ❄️ Dormant |
| Nov | — | 0.9" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Rolette County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Onion Planting Timeline — Rolette County, ND
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 5 | Apr 5 – Apr 19 |
| Transplant Outdoors | May 17 | May 17 – May 31 |
| Direct Sow | May 10 | May 10 – May 31 |
| Harvest | August 16 | Aug 16 – Sep 20 |
| Fall Sowing | June 30 | Jun 30 – Jul 14 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Fall Sowing |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 3b
📆 Growing Season
128 days in Rolette County
Growing Tips for Rolette County
Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Rolette County, ND?
Rolette County is in Zone 3b with an average last frost of May 17. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rolette County, ND?
Rolette County, North Dakota is in USDA Hardiness Zone 3b. The average last spring frost is May 17 and first fall frost is September 22.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Rolette County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.
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