When to Plant Lettuce in Tillamook County, OR
Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.
Tillamook County, Oregon is in USDA Zone 8b. The average last spring frost is April 19 and the first fall frost is October 29, giving you a growing season of approximately 193 days.
At an elevation of 332 feet, Tillamook County receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Lettuce during the growing season.
Tillamook County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.5
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 Tillamook County
How your county's soil matches Lettuce's growing requirements.
Soil pH
Your soil pH (5.3–6.5) is more acidic than Lettuce prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Tillamook County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.3%) — Lettuce will thrive.
How to Plant Lettuce
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Lettuce
Sow every 3.4 weeks. Last sowing by Aug 30 to harvest before frost.
For a dedicated fall crop, sow by Aug 20.
Plant Water Budget
Monthly Watering Guide for Lettuce
Lettuce needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Lettuce Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.4" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | — | 4.1" | 0" | ❄️ Dormant |
| Apr | 3" | 3.4" | 0" | ✅ Rainfall sufficient |
| May | 3" | 2.5" | 0.5" | 💧 Light watering |
| Jun | 3" | 1.8" | 1.2" | 💧 Light watering |
| Jul | 3" | 0.7" | 2.3" | 🚿 Regular watering |
| Aug | 3" | 0.8" | 2.2" | 🚿 Regular watering |
| Sep | 3" | 1.8" | 1.2" | 💧 Light watering |
| Oct | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Nov | — | 6.4" | 0" | ❄️ Dormant |
| Dec | — | 6.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Tillamook County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lettuce 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.
Lettuce Planting Timeline — Tillamook County, OR
Lettuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | April 19 | Apr 19 – May 3 |
| Direct Sow | April 5 | Apr 5 – Apr 26 |
| Harvest | May 24 | May 24 – Aug 2 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
30–60 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
193 days in Tillamook County
Growing Tips for Lettuce in Tillamook County
Direct sow Lettuce outdoors after April 19 in Tillamook County when soil has warmed and frost danger has passed.
Your generous 193.0-day season in Tillamook County allows multiple plantings of Lettuce. Sow every 15.0 days for continuous harvest.
Common pests for Lettuce in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.
Recommended Lettuce Varieties for Tillamook County
Bolt-resistant varieties for warm summers — grow as spring/fall crop
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Very easy to save. Let a few plants bolt each season.
Lettuce in Other Locations
Frequently Asked Questions
When should I plant Lettuce in Tillamook County, OR?
Tillamook County is in Zone 8b with an average last frost of April 19. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Tillamook County, OR?
Tillamook County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 19 and first fall frost is October 29.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Tillamook County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.
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