When to Plant Cranberries in Malheur County, OR
Malheur County, Oregon gardeners: here's your May plan
Welcome to May in Zone 6b. These are the moves that will have the biggest impact on your growing season.
June will be here before you know it — start on
- Transplants going out: cranberries
Cranberries are low-growing, vine-like shrubs that produce tart red berries in fall. They grow in acidic, boggy conditions and are surprisingly easy to cultivate.
Malheur County, Oregon is in USDA Zone 6b. The average last spring frost is May 18 and the first fall frost is September 29, giving you a growing season of approximately 134 days.
At an elevation of 2,676 feet, Malheur County receives approximately 17.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Cranberries during the growing season. With low rainfall, drip irrigation is essential for growing Cranberries successfully. Mulch heavily to conserve soil moisture.
Malheur County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.3
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 Malheur County
How your county's soil matches Cranberries's growing requirements.
Soil pH
Your soil pH (5.4–6.3) is more alkaline than Cranberries prefers (4.0–5.5). Add sulfur or peat moss to lower pH.
Soil Texture
The silt loam soil in Malheur County is excellent for Cranberries — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Cranberries is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is excellent (5.6%) — Cranberries will thrive.
How to Plant Cranberries
Plant Water Budget
Monthly Watering Guide for Cranberries
Cranberries needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Cranberries Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 1.2" | 0" | ❄️ Dormant |
| May | 6.5" | 0.9" | 5.6" | 🚿 Regular watering |
| Jun | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Jul | 6.5" | 0.3" | 6.2" | 🚿 Regular watering |
| Aug | 6.5" | 0.3" | 6.2" | 🚿 Regular watering |
| Sep | 6.5" | 0.8" | 5.7" | 🚿 Regular watering |
| Oct | — | 1.4" | 0" | ❄️ Dormant |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 3.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Malheur County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cranberries 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.
Cranberries Planting Timeline — Malheur County, OR
Cranberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 8 | Jun 8 – Jun 22 |
· 36" apart · Rows 48" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
730–1095 days
🧪 Soil pH
Needs 4–5.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 6b
📆 Growing Season
134 days in Malheur County
Growing Tips for Cranberries in Malheur County
Direct sow Cranberries outdoors after May 18 in Malheur County when soil has warmed and frost danger has passed.
Your 134.0-day growing season in Malheur County is tight for Cranberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.
Malheur County receives only 18" of rain annually. Cranberries needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Create an acidic, consistently moist bed with peat moss. Cranberries do not need to be flooded to grow; flooding is only used for commercial harvesting. Mulch with sand in early spring.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Cranberries in Other Locations
Frequently Asked Questions
When should I plant Cranberries in Malheur County, OR?
Malheur County is in Zone 6b with an average last frost of May 18. Plan your Cranberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is Malheur County, OR?
Malheur County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is May 18 and first fall frost is September 29.
Your Malheur County Garden Planner — Free
A 24-page printable planner built for Malheur County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.