When to plant Onion in Daniels County County,
Spring Onion in Daniels County County goes in May 13–June 3, once nighttime temps stop dipping near freezing. A second sowing from June 24 to July 8 extends the harvest into fall.
When to Plant Onion in Daniels County, MT
What to do in June
Your garden in Daniels County, Montana is working on a schedule, even when you're not. Here's where you should be this June.
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Start your fall crops: onion
Fall crops get sweeter with a light frost. Don't be afraid of cool nights.
July prep starts now
- Starting indoors: onion
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.
Daniels County, Montana is in USDA Zone 3b. The average last spring frost is May 20 and the first fall frost is September 16, giving you a growing season of approximately 119 days.
At an elevation of 6,023 feet, Daniels County receives approximately 15.5 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. With low rainfall, drip irrigation is essential for growing Onion successfully. Mulch heavily to conserve soil moisture.
Daniels County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.8
Drainage
Well Drained
Onion 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.
Soil Compatibility in Daniels County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (6.3–7.8) is more alkaline than Onion prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Daniels County is excellent for Onion — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Onion.
How to Plant Onion
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Onion Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Jun | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Jul | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Aug | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Sep | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Oct | — | 1.3" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Daniels County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Onion 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.
Onion Planting Timeline — Daniels County, MT
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 8 | Apr 8 – Apr 22 |
| Transplant Outdoors | May 20 | May 20 – Jun 3 |
| Direct Sow | May 13 | May 13 – Jun 3 |
| Harvest | August 19 | Aug 19 – Sep 23 |
| Fall Sowing | June 24 | Jun 24 – Jul 8 |
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 | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 3b
📆 Growing Season
119 days in Daniels County
Growing Tips for Onion in Daniels County
Direct sow Onion outdoors after May 20 in Daniels County when soil has warmed and frost danger has passed.
Your 119.0-day growing season in Daniels County is tight for Onion (90.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Onion in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
Daniels County receives only 16" of rain annually. Onion needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
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 Daniels County, MT?
Daniels County is in Zone 3b with an average last frost of May 20. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Daniels County, MT?
Daniels County, Montana is in USDA Hardiness Zone 3b. The average last spring frost is May 20 and first fall frost is September 16.
When should I plant Onion in Daniels County County, ?
In Daniels County County, , plant Onion after the last frost (around May 20) and before the first frost (around September 16). Best results when soil holds above 50°F.
What growing zone is Daniels County County, for Onion?
Daniels County County sits in USDA Zone 3b. Onion grows reliably in zones 3a through 10b, so it's a good fit here.
Can Onion grow in Daniels County County's climate?
Yes — Onion grows well in Daniels County County's temperate climate. Daniels County County averages a 119-day frost-free season, with last frost around May 20 and first frost around September 16.
Your Daniels County Garden Planner — Free
A 22-page printable planner built for Daniels County (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.