When to Plant Komatsuna in Big Horn County, WY
May in the garden — Big Horn County, Wyoming
Here's what deserves your attention in Big Horn County, Wyoming this month. Everything below is tailored to Zone 5a and timed around your local frost dates.
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Move komatsuna into the garden
Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.
Coming up in June — start thinking about
- Starting indoors: komatsuna
- First harvests: komatsuna
Komatsuna (Japanese mustard spinach) is a versatile Asian green with glossy, dark leaves and a mild, sweet flavor. It is extremely cold-hardy and heat-tolerant.
Big Horn County, Wyoming is in USDA Zone 5a. The average last spring frost is May 9 and the first fall frost is October 2, giving you a growing season of approximately 146 days.
At an elevation of 7,668 feet, Big Horn County receives approximately 13.7 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Komatsuna to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Komatsuna successfully. Mulch heavily to conserve soil moisture.
Big Horn County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.7
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 Big Horn County
How your county's soil matches Komatsuna's growing requirements.
Soil pH
Your soil pH (6.2–7.7) overlaps with Komatsuna's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Big Horn County is excellent for Komatsuna — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Komatsuna.
How to Plant Komatsuna
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Komatsuna
Sow every 4 weeks. Last sowing by Aug 13 to harvest before frost.
For a dedicated fall crop, sow by Jul 24.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Komatsuna
Komatsuna needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Komatsuna Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.9" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.2" | 0" | ❄️ Dormant |
| Apr | — | 1.4" | 0" | ❄️ Dormant |
| May | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Jun | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Jul | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Aug | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Sep | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Oct | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Big Horn County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Komatsuna 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.
Komatsuna Planting Timeline — Big Horn County, WY
Komatsuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 4 | Apr 4 – Apr 18 |
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Direct Sow | April 25 | Apr 25 – May 16 |
| Harvest | June 13 | Jun 13 – Jul 18 |
| Fall Sowing | July 24 | Jul 24 – Aug 7 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | 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: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
146 days in Big Horn County
Growing Tips for Komatsuna in Big Horn County
Direct sow Komatsuna outdoors after May 09 in Big Horn County when soil has warmed and frost danger has passed.
Your generous 146.0-day season in Big Horn County allows multiple plantings of Komatsuna. Sow every 17.0 days for continuous harvest.
Common pests for Komatsuna in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
Big Horn County receives only 14" of rain annually. Komatsuna needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow in spring or fall. One of the most forgiving Asian greens for all seasons. Harvest outer leaves or cut whole plants. Excellent for stir-fries, soups, or salads.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Komatsuna in Other Locations
Frequently Asked Questions
When should I plant Komatsuna in Big Horn County, WY?
Big Horn County is in Zone 5a with an average last frost of May 9. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Big Horn County, WY?
Big Horn County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 9 and first fall frost is October 2.
Your Big Horn County Garden Planner — Free
A 24-page printable planner built for Big Horn County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.