When to Plant Cauliflower in Clatsop County, OR
May in Clatsop County, Oregon — your action list
Your Clatsop County, Oregon garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Fire up the seed-starting tray: cauliflower
You're about 25 weeks out from your last frost — the perfect window to get these germinating indoors.
To set up a strong June, finish these tasks
- First harvests: cauliflower
Cauliflower is a cool-season brassica that produces dense white, purple, or green heads called curds. It is more finicky than broccoli but rewards with a mild, nutty flavor.
Clatsop County, Oregon is in USDA Zone 9a. The average last spring frost is April 12 and the first fall frost is November 4, giving you a growing season of approximately 206 days.
At an elevation of 412 feet, Clatsop County receives approximately 54.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Cauliflower during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cauliflower root diseases.
Clatsop County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
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 Clatsop County
How your county's soil matches Cauliflower's growing requirements.
Soil pH
Your soil pH (5.6–6.7) overlaps with Cauliflower's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Clatsop County is excellent for Cauliflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.9%) — Cauliflower will thrive.
How to Plant Cauliflower
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Cauliflower
Sow every 6.3 weeks. Last sowing by Jul 27 to harvest before frost.
For a dedicated fall crop, sow by Sep 09.
Plant Water Budget
Monthly Watering Guide for Cauliflower
Cauliflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Cauliflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 8.4" | 0" | ❄️ Dormant |
| Feb | — | 5.2" | 0" | ❄️ Dormant |
| Mar | — | 4.8" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| May | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Jun | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Jul | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Aug | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Sep | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Oct | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Nov | 4.3" | 8.4" | 0" | ✅ Rainfall sufficient |
| Dec | — | 9.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Clatsop County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cauliflower 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.
Cauliflower Planting Timeline — Clatsop County, OR
Cauliflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | April 12 | Apr 12 – Apr 26 |
| Direct Sow | March 22 | Mar 22 – Apr 12 |
| Harvest | June 7 | Jun 7 – Aug 9 |
| Fall Sowing | September 9 | Sep 9 – Sep 23 |
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
1"/week · Natural rainfall sufficient
📅 Days to Maturity
55–100 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
206 days in Clatsop County
Growing Tips for Cauliflower in Clatsop County
Direct sow Cauliflower outdoors after April 12 in Clatsop County when soil has warmed and frost danger has passed.
Common pests for Cauliflower 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 6 weeks before transplanting. Blanch white varieties by tying outer leaves over the head. Provide consistent moisture and avoid temperature extremes.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cauliflower in Other Locations
Frequently Asked Questions
When should I plant Cauliflower in Clatsop County, OR?
Clatsop County is in Zone 9a with an average last frost of April 12. Plan your Cauliflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clatsop County, OR?
Clatsop County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is April 12 and first fall frost is November 4.
Your Clatsop County Garden Planner — Free
A 24-page printable planner built for Clatsop 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.