When to Plant Tatsoi in Malheur 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.
Malheur County, Oregon is in USDA Zone 6a. 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 Tatsoi during the growing season. With low rainfall, drip irrigation is essential for growing Tatsoi 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 Tatsoi's growing requirements.
Soil pH
Your soil pH (5.4–6.3) is more acidic than Tatsoi prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Malheur County is excellent for Tatsoi — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Tatsoi.
Organic Matter
Organic matter is excellent (5.6%) — Tatsoi will thrive.
How to Plant Tatsoi
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Tatsoi
Sow every 4 weeks. Last sowing by Aug 10 to harvest before frost.
For a dedicated fall crop, sow by Jul 21.
Plant Water Budget
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 | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 1.2" | 0" | ❄️ Dormant |
| May | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Jun | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Jul | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Aug | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Sep | 4.3" | 0.8" | 3.5" | 🚿 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.
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" — 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.
Tatsoi Planting Timeline — Malheur County, OR
Tatsoi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 13 | Apr 13 – Apr 27 |
| Transplant Outdoors | May 18 | May 18 – Jun 1 |
| Direct Sow | May 4 | May 4 – May 25 |
| Harvest | June 22 | Jun 22 – Jul 27 |
| Fall Sowing | July 21 | Jul 21 – Aug 4 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6a
📆 Growing Season
134 days in Malheur County
Growing Tips for Tatsoi in Malheur County
Direct sow Tatsoi outdoors after May 18 in Malheur County when soil has warmed and frost danger has passed.
Your generous 134.0-day season in Malheur 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.
Malheur County receives only 18" of rain annually. Tatsoi needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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
Check more plant combinations with our Companion Planting Checker →
Tatsoi in Other Locations
Frequently Asked Questions
When should I plant Tatsoi in Malheur County, OR?
Malheur County is in Zone 6a with an average last frost of May 18. Plan your Tatsoi 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 6a. The average last spring frost is May 18 and first fall frost is September 29.
Plan Your Garden with Confidence
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