When to Plant Tatsoi in Powder River County, MT
What to do in May
Here's what deserves your attention in Powder River County, Montana this month. Everything below is tailored to Zone 4b and timed around your local frost dates.
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Move tatsoi from tray to bed
Frost risk is low now in Powder River County, Montana. If you've been covering beds overnight, you can stop.
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Direct-sow tatsoi
Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.
A few tasks this May that'll pay off in June
- Starting indoors: tatsoi
- First harvests: tatsoi
- Fall sowing: tatsoi
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.
Powder River County, Montana is in USDA Zone 4b. The average last spring frost is May 15 and the first fall frost is September 22, giving you a growing season of approximately 130 days.
At an elevation of 6,328 feet, Powder River County receives approximately 19.4 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Tatsoi to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Tatsoi successfully. Mulch heavily to conserve soil moisture.
Powder River County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.9
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 Powder River County
How your county's soil matches Tatsoi's growing requirements.
Soil pH
Your soil pH (6.5–7.9) overlaps with Tatsoi's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Powder River County is excellent for Tatsoi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Tatsoi.
How to Plant Tatsoi
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Tatsoi
Sow every 4 weeks. Last sowing by Aug 03 to harvest before frost.
For a dedicated fall crop, sow by Jun 30.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Jun | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Jul | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Aug | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Sep | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Oct | — | 1.6" | 0" | ❄️ Dormant |
| Nov | — | 1.3" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Powder River 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 — Powder River County, MT
Tatsoi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 3 | Apr 3 – Apr 17 |
| Transplant Outdoors | May 15 | May 15 – May 29 |
| Direct Sow | May 8 | May 8 – May 29 |
| Harvest | June 19 | Jun 19 – Jul 24 |
| Fall Sowing | June 30 | Jun 30 – Jul 14 |
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 | Fall Sowing Harvest |
| July | Fall Sowing Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 4b
📆 Growing Season
130 days in Powder River County
Growing Tips for Tatsoi in Powder River County
Direct sow Tatsoi outdoors after May 15 in Powder River County when soil has warmed and frost danger has passed.
Your generous 130.0-day season in Powder River 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.
Powder River County receives only 19" 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 Powder River County, MT?
Powder River County is in Zone 4b with an average last frost of May 15. Plan your Tatsoi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Powder River County, MT?
Powder River County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 15 and first fall frost is September 22.
Your Powder River County Garden Planner — Free
A 24-page printable planner built for Powder River County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.