When to plant Arugula in Phillips County, MT
Plant Arugula in Phillips County after May 18; the prime window is May 11–June 1. A second sowing from June 29 to July 13 extends the harvest into fall.
When to Plant Arugula in Phillips County, MT
June in the garden — Phillips County, Montana
Your Phillips County, Montana garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
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Sow arugula in trays indoors
You're about 13 weeks out from your last frost — the perfect window to get these germinating indoors.
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Collect arugula at their peak
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
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Direct-sow arugula for cool weather
Count back from your first frost (September 21) — these need to mature before the cold arrives.
Coming up in July — start thinking about
- First harvests: arugula
Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.
Phillips County, Montana is in USDA Zone 3b. The average last spring frost is May 18 and the first fall frost is September 21, giving you a growing season of approximately 126 days.
At an elevation of 6,886 feet, Phillips County receives approximately 19 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Arugula to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Arugula successfully. Mulch heavily to conserve soil moisture.
Phillips County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.6
Drainage
Well Drained
Arugula 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 Phillips County
How your county's soil matches Arugula's growing requirements.
Soil pH
Your soil pH (6.7–7.6) is more alkaline than Arugula prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Phillips County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Arugula.
How to Plant Arugula
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Arugula
Sow every 3.4 weeks. Last sowing by Aug 02 to harvest before frost.
For a dedicated fall crop, sow by Jun 29.
Arugula Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Arugula
Arugula needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.
| Month | Arugula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 2.6" | 2.4" | 0.2" | 💧 Light watering |
| Jun | 2.6" | 1.4" | 1.2" | 💧 Light watering |
| Jul | 2.6" | 1.6" | 1" | 💧 Light watering |
| Aug | 2.6" | 2" | 0.6" | 💧 Light watering |
| Sep | 2.6" | 1.4" | 1.2" | 💧 Light watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 1.3" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Phillips County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Arugula 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.
Arugula Planting Timeline — Phillips County, MT
Arugula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 6 | Apr 6 – Apr 20 |
| Transplant Outdoors | May 18 | May 18 – Jun 1 |
| Direct Sow | May 11 | May 11 – Jun 1 |
| Harvest | June 22 | Jun 22 – Aug 24 |
| Fall Sowing | June 29 | Jun 29 – Jul 13 |
Plant 0.5" 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 Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.6"/week · Natural rainfall sufficient
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 3b
📆 Growing Season
126 days in Phillips County
Growing Tips for Arugula in Phillips County
Direct sow Arugula outdoors after May 18 in Phillips County when soil has warmed and frost danger has passed.
Your generous 126.0-day season in Phillips County allows multiple plantings of Arugula. Sow every 15.0 days for continuous harvest.
Common pests for Arugula in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Arugula in Other Locations
Frequently Asked Questions
When should I plant Arugula in Phillips County, MT?
Phillips County is in Zone 3b with an average last frost of May 18. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Phillips County, MT?
Phillips County, Montana is in USDA Hardiness Zone 3b. The average last spring frost is May 18 and first fall frost is September 21.
When should I plant Arugula in Phillips County, MT?
In Phillips County, MT, plant Arugula after the last frost (around May 18) and before the first frost (around September 21). Best results when soil holds above 50°F.
What growing zone is Phillips County, MT for Arugula?
Phillips County sits in USDA Zone 3b. Arugula grows reliably in zones 3a through 11b, so it's a good fit here.
Can Arugula grow in Phillips County's climate?
Yes — Arugula grows well in Phillips County's temperate climate. Phillips County averages a 126-day frost-free season, with last frost around May 18 and first frost around September 21.
Your Phillips County Garden Planner — Free
A 22-page printable planner built for Phillips 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.