When to Plant Cabbage in Clackamas County, OR
What to do in May
Your garden in Clackamas County, Oregon is working on a schedule, even when you're not. Here's where you should be this May.
-
Start cabbage under lights
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
Coming up in June — start thinking about
- First harvests: cabbage
Cabbage is a versatile cool-season crop that forms dense, leafy heads in green, red, or savoy varieties. It is a staple for coleslaw, sauerkraut, and many global cuisines.
Clackamas County, Oregon is in USDA Zone 9a. The average last spring frost is April 14 and the first fall frost is October 28, giving you a growing season of approximately 197 days.
At an elevation of 199 feet, Clackamas County receives approximately 53.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Cabbage during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cabbage root diseases.
Clackamas County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.3
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 Clackamas County
How your county's soil matches Cabbage's growing requirements.
Soil pH
Your soil pH (5.7–6.3) overlaps with Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Clackamas County is excellent for Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.7%) — Cabbage will thrive.
How to Plant Cabbage
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Cabbage
Sow every 6.9 weeks. Last sowing by Jul 20 to harvest before frost.
For a dedicated fall crop, sow by Sep 02.
Plant Water Budget
Monthly Watering Guide for Cabbage
Cabbage needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.
| Month | Cabbage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 8.3" | 0" | ❄️ Dormant |
| Feb | — | 5.3" | 0" | ❄️ Dormant |
| Mar | — | 4.8" | 0" | ❄️ Dormant |
| Apr | 3.9" | 4" | 0" | ✅ Rainfall sufficient |
| May | 3.9" | 3.3" | 0.6" | 💧 Light watering |
| Jun | 3.9" | 2.1" | 1.8" | 💧 Light watering |
| Jul | 3.9" | 0.8" | 3.1" | 🚿 Regular watering |
| Aug | 3.9" | 1" | 2.9" | 🚿 Regular watering |
| Sep | 3.9" | 2.2" | 1.7" | 💧 Light watering |
| Oct | 3.9" | 4.7" | 0" | ✅ Rainfall sufficient |
| Nov | — | 8.2" | 0" | ❄️ Dormant |
| Dec | — | 8.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clackamas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cabbage 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.
Cabbage Planting Timeline — Clackamas County, OR
Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | March 24 | Mar 24 – Apr 14 |
| Harvest | June 16 | Jun 16 – Aug 11 |
| Fall Sowing | September 2 | Sep 2 – Sep 16 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · Natural rainfall sufficient
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
197 days in Clackamas County
Growing Tips for Cabbage in Clackamas County
Direct sow Cabbage outdoors after April 14 in Clackamas County when soil has warmed and frost danger has passed.
Common pests for Cabbage in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 4-6 weeks before last frost. Space plants 18-24 inches apart. Keep soil evenly moist to prevent heads from splitting.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cabbage in Other Locations
Frequently Asked Questions
When should I plant Cabbage in Clackamas County, OR?
Clackamas County is in Zone 9a with an average last frost of April 14. Plan your Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clackamas County, OR?
Clackamas County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is April 14 and first fall frost is October 28.
Your Clackamas County Garden Planner — Free
A 24-page printable planner built for Clackamas County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.