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When to Plant Tatsoi in Tillamook County, OR

Tatsoi is a compact Asian green forming beautiful rosettes of dark, spoon-shaped leaves with a mild mustard flavor. It is extremely cold-hardy and versatile.

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 85ยฐF, providing good warmth for Tatsoi during the growing season.

Tillamook County, OR (Zone 8b) Moderate season
193 days
Last Spring Frost April 19
193 growing days
First Fall Frost October 29

Tillamook County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (125 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: May 17 – Jun 21
Recommended (50%) ✓ Fits season (123 days to spare)
Start indoors: Mar 15 Transplant: Apr 19 🍅 Harvest: May 24 – Jun 28
Safe Start (90%) ✓ Fits season (122 days to spare)
Start indoors: Apr 3 Transplant: May 8 🍅 Harvest: Jun 12 – Jul 17

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 Tatsoi's growing requirements.

Soil pH

Your soil pH (5.3โ€“6.5) is more acidic than Tatsoi prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Tillamook County is excellent for Tatsoi โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.3%) โ€” Tatsoi will thrive.

How to Plant Tatsoi

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Tatsoi

6
successive plantings in your 193-day season

Sow every 4 weeks. Last sowing by Sep 09 to harvest before frost.

For a dedicated fall crop, sow by Aug 20.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 193 gal / 100 sq ft

Monthly Watering Guide for Tatsoi

Tatsoi needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Tatsoi Needs Rainfall You Supplement Action
Jan โ€” 5.4" 0" โ„๏ธ Dormant
Feb โ€” 4.1" 0" โ„๏ธ Dormant
Mar โ€” 4.1" 0" โ„๏ธ Dormant
Apr 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
May 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Jun 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering
Jul 4.3" 0.7" 3.6" ๐Ÿšฟ Regular watering
Aug 4.3" 0.8" 3.5" ๐Ÿšฟ Regular watering
Sep 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering
Oct 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Nov โ€” 6.4" 0" โ„๏ธ Dormant
Dec โ€” 6.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Tillamook County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Tatsoi 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" โ€” every day above 50ยฐF 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.

Tatsoi needs ~584 GDD — county provides 2,653 GDD Excellent fit

Tatsoi Planting Timeline โ€” Tillamook County, OR

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 โ€“ Mar 29
Transplant Outdoors April 19 Apr 19 โ€“ May 3
Direct Sow April 5 Apr 5 โ€“ Apr 26
Harvest May 24 May 24 โ€“ Jun 28
Fall Sowing August 20 Aug 20 โ€“ Sep 3

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Harvest
June Harvest
July โ€”
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

193 days in Tillamook County

Growing Tips for Tatsoi in Tillamook County

Direct sow Tatsoi 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 Tatsoi. Sow every 17.0 days for continuous harvest.

Common pests for Tatsoi in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Tatsoi tolerates frost down to 15F. Harvest outer leaves or cut whole rosettes. Excellent in salads, stir-fries, or lightly wilted.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Tatsoi in Tillamook County, OR?

Tillamook County is in Zone 8b with an average last frost of April 19. Plan your Tatsoi planting based on this frost date โ€” 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.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Tillamook County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Tillamook County, OR. Local conditions may vary. Last updated: April 2026.