When to Plant Rosemary in Jefferson County, OR
Your June game plan for Jefferson County, Oregon
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
-
Get rosemary in the ground
Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.
Rosemary is an aromatic evergreen shrub with needle-like leaves and a piney, citrus flavor. It is a Mediterranean herb that thrives in warm, dry conditions.
Jefferson County, Oregon is in USDA Zone 7a. The average last spring frost is June 9 and the first fall frost is September 19, giving you a growing season of approximately 102 days.
At an elevation of 21 feet, Jefferson County receives approximately 36.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79°F, so choose short-season varieties of Rosemary to ensure they mature before fall.
Jefferson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.7
Drainage
Well Drained
Rosemary 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 Jefferson County
How your county's soil matches Rosemary's growing requirements.
Soil pH
Your soil pH (5.3–6.7) overlaps with Rosemary's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Jefferson County is excellent for Rosemary — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.0%) — Rosemary will thrive.
How to Plant Rosemary
Rosemary Water Budget
Monthly Watering Guide for Rosemary
Rosemary 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 | Rosemary Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.8" | 0" | ❄️ Dormant |
| Feb | — | 3.7" | 0" | ❄️ Dormant |
| Mar | — | 3.7" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | — | 1.8" | 0" | ❄️ Dormant |
| Jun | 1.3" | 1.6" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 0.5" | 0.8" | 🚿 Regular watering |
| Aug | 1.3" | 0.6" | 0.7" | 🚿 Regular watering |
| Sep | 1.3" | 1.6" | 0" | ✅ Rainfall sufficient |
| Oct | — | 3.2" | 0" | ❄️ Dormant |
| Nov | — | 6.1" | 0" | ❄️ Dormant |
| Dec | — | 5.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Rosemary 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.
Rosemary Planting Timeline — Jefferson County, OR
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 16 | Jun 16 – Jun 30 |
| Harvest | September 8 | Sep 8 – Jan 26 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Harvest |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| July | — |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | Harvest |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
80–180 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
102 days in Jefferson County
Growing Tips for Rosemary in Jefferson County
Direct sow Rosemary outdoors after June 09 in Jefferson County when soil has warmed and frost danger has passed.
Your 102.0-day growing season in Jefferson County is tight for Rosemary (80.0-180.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
Grow in well-drained soil and avoid overwatering. In cold climates, grow in containers and bring indoors for winter. Propagate from stem cuttings for faster results than seed.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Rosemary in Other Locations
Frequently Asked Questions
When should I plant Rosemary in Jefferson County, OR?
Jefferson County is in Zone 7a with an average last frost of June 9. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, OR?
Jefferson County, Oregon is in USDA Hardiness Zone 7a. The average last spring frost is June 9 and first fall frost is September 19.
Your Jefferson County Garden Planner — Free
A 22-page printable planner built for Jefferson County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.