When to Plant Arugula in Harney County, OR
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.
Harney County, Oregon is in USDA Zone 5b. The average last spring frost is June 17 and the first fall frost is September 6, giving you a growing season of approximately 81 days.
At an elevation of 679 feet, Harney County receives approximately 22.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Arugula during the growing season.
Harney County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.4
Drainage
Well Drained
Plant 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 Harney County
How your county's soil matches Arugula's growing requirements.
Soil pH
Your soil pH (5.6–6.4) overlaps with Arugula's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Harney County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.5%) — Arugula will thrive.
How to Plant Arugula
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Arugula
Sow every 3.4 weeks. Last sowing by Jul 18 to harvest before frost.
For a dedicated fall crop, sow by Jun 28.
Plant 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 | — | 3.3" | 0" | ❄️ Dormant |
| Feb | — | 2.2" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 1.5" | 0" | ❄️ Dormant |
| May | — | 1.4" | 0" | ❄️ Dormant |
| Jun | 2.6" | 0.9" | 1.7" | 🚿 Regular watering |
| Jul | 2.6" | 0.4" | 2.2" | 🚿 Regular watering |
| Aug | 2.6" | 0.4" | 2.2" | 🚿 Regular watering |
| Sep | 2.6" | 0.9" | 1.7" | 🚿 Regular watering |
| Oct | — | 2" | 0" | ❄️ Dormant |
| Nov | — | 3.6" | 0" | ❄️ Dormant |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Harney 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 — Harney County, OR
Arugula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 13 | May 13 – May 27 |
| Transplant Outdoors | June 17 | Jun 17 – Jul 1 |
| Direct Sow | June 3 | Jun 3 – Jun 24 |
| Harvest | July 22 | Jul 22 – Sep 23 |
| Fall Sowing | June 28 | Jun 28 – Jul 12 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Transplant Outdoors Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| 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: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
81 days in Harney County
Growing Tips for Arugula in Harney County
Direct sow Arugula outdoors after June 17 in Harney County when soil has warmed and frost danger has passed.
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 Harney County, OR?
Harney County is in Zone 5b with an average last frost of June 17. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harney County, OR?
Harney County, Oregon is in USDA Hardiness Zone 5b. The average last spring frost is June 17 and first fall frost is September 6.
Plan Your Garden with Confidence
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