When to Plant Oregano in Marion County, OR
Oregano is a robust perennial herb essential to Italian and Greek cuisine. Its pungent, savory leaves intensify in flavor when dried.
Marion County, Oregon is in USDA Zone 8a. The average last spring frost is April 20 and the first fall frost is October 30, giving you a growing season of approximately 193 days.
At an elevation of 422 feet, Marion County receives approximately 50.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Oregano during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Oregano root diseases.
Marion County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.8
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 Marion County
How your county's soil matches Oregano's growing requirements.
Soil pH
Your soil pH (5.4–6.8) overlaps with Oregano's range (6.0–8.0), though not a perfect match.
Soil Texture
The silt loam soil in Marion County is excellent for Oregano — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Oregano will thrive.
How to Plant Oregano
Succession Planting Oregano
Sow every 6.9 weeks. Last sowing by Aug 01 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Oregano
Oregano needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.
| Month | Oregano Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6.9" | 0" | ❄️ Dormant |
| Feb | — | 5.1" | 0" | ❄️ Dormant |
| Mar | — | 4.9" | 0" | ❄️ Dormant |
| Apr | 1.3" | 3.8" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 2.8" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 2" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 0.8" | 0.5" | 💧 Light watering |
| Aug | 1.3" | 1" | 0.3" | 💧 Light watering |
| Sep | 1.3" | 1.9" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 4.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 8.2" | 0" | ❄️ Dormant |
| Dec | — | 9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Marion County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Oregano 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.
Oregano Planting Timeline — Marion County, OR
Oregano Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Harvest | June 29 | Jun 29 – Sep 7 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–8 · Your soil: acceptable
🗺️ USDA Zone
Zone 8a
📆 Growing Season
193 days in Marion County
Growing Tips for Oregano in Marion County
Direct sow Oregano outdoors after April 20 in Marion County when soil has warmed and frost danger has passed.
General growing tips
Start from seed, cuttings, or divisions. Harvest just before flowering for strongest flavor. Cut plants back to a few inches in spring to encourage vigorous new growth.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Oregano in Other Locations
Frequently Asked Questions
When should I plant Oregano in Marion County, OR?
Marion County is in Zone 8a with an average last frost of April 20. Plan your Oregano planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marion County, OR?
Marion County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is April 20 and first fall frost is October 30.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Marion County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.
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