When to Plant Rosemary in Morrow County, OR
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.
Morrow County, Oregon is in USDA Zone 7b. The average last spring frost is April 25 and the first fall frost is October 15, giving you a growing season of approximately 173 days.
At an elevation of 2,335 feet, Morrow County receives approximately 20.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Rosemary during the growing season.
Morrow County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.8
Drainage
Well Drained
Monthly Watering Guide for Rosemary
Rosemary needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Rosemary Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3" | 0" | ❄️ Dormant |
| Feb | — | 2.8" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| May | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Jun | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Jul | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Aug | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Sep | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Oct | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Nov | — | 3.2" | 0" | ❄️ Dormant |
| Dec | — | 3.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Morrow County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Rosemary Planting Timeline — Morrow County, OR
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Harvest | July 25 | Jul 25 – Dec 12 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | Harvest |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
80–180 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 7b
📆 Growing Season
173 days in Morrow County
Growing Tips for Morrow County
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 Morrow County, OR?
Morrow County is in Zone 7b with an average last frost of April 25. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is Morrow County, OR?
Morrow County, Oregon is in USDA Hardiness Zone 7b. The average last spring frost is April 25 and first fall frost is October 15.
Your Morrow County Garden Planner — Free
A 22-page printable planner built for Morrow County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.