When to Plant Peonies in Morrow County, OR
Peonies (Paeonia lactiflora) are the crown jewels of the spring garden — magnificent, fragrant blooms in white, pink, and red that can last 100 years or more in the same spot with minimal care. Extremely cold-hardy and requiring a period of winter chill to bloom, they are most productive in Zones 3–7. Each established clump produces dozens of lush, fully double or semi-double flowers over a 2–3 week window in late spring. Virtually pest-free beyond the cosmetic presence of ants on buds (which are harmless). Once sited correctly, peonies rarely need dividing or moving.
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 Peonies 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 Peonies
Peonies needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Peonies 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.
Peonies Planting Timeline — Morrow County, OR
Peonies Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Bloom | June 27 | Jun 27 – Jul 25 |
Plant 1.5" deep · 36" apart · Rows 48" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6.5–7 · Your soil: N/A
🗺️ USDA Zone
Zone 7b
📆 Growing Season
173 days in Morrow County
Growing Tips for Morrow County
Plant bare-root divisions in fall (late September through October in Zones 3–7; November in Zone 8) with eyes facing upward and positioned exactly 1–2 inches below soil surface — deeper planting is the most common reason peonies fail to bloom. Choose a site with full sun and excellent drainage. Peonies require 6+ weeks of temperatures below 40°F (cold stratification period) for reliable bloom — they do not perform well in Zone 9+. Do not expect full bloom the first or second year; Year 3+ plants deliver the most impressive flowering. Avoid moving established plants. Stake double- flowered types before heavy blooms cause stems to flop. Cut stems to ground in fall after frost kills foliage to prevent botrytis overwinter.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Peonies in Other Locations
Frequently Asked Questions
When should I plant Peonies in Morrow County, OR?
Morrow County is in Zone 7b with an average last frost of April 25. Plan your Peonies 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.