When to Plant Komatsuna in Morgan County, UT
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.
Morgan County, Utah is in USDA Zone 5b. The average last spring frost is June 17 and the first fall frost is August 31, giving you a growing season of approximately 75 days.
At an elevation of 6,439 feet, Morgan County receives approximately 14.4 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.
Morgan County Soil Profile
Soil Type
Loam
Soil pH
6.5-8.1
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 Morgan County
How your county's soil matches Komatsuna's growing requirements.
Soil pH
Your soil pH (6.5–8.1) overlaps with Komatsuna's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Morgan County is excellent for Komatsuna — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Komatsuna.
Organic Matter
Organic matter is moderate (2.5%). 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 Jul 12 to harvest before frost.
For a dedicated fall crop, sow by Jun 22.
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 | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.2" | 0" | ❄️ Dormant |
| Apr | — | 1.4" | 0" | ❄️ Dormant |
| May | — | 1.8" | 0" | ❄️ Dormant |
| Jun | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Jul | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Aug | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Sep | — | 1.2" | 0" | ❄️ Dormant |
| Oct | — | 1.1" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Aug in Morgan 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 — Morgan County, UT
Komatsuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 13 | May 13 – May 27 |
| Transplant Outdoors | June 17 | Jun 17 – Jul 1 |
| Direct Sow | June 3 | Jun 3 – Jun 24 |
| Harvest | July 22 | Jul 22 – Aug 26 |
| Fall Sowing | June 22 | Jun 22 – Jul 6 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Transplant Outdoors Fall Sowing Harvest |
| August | Harvest |
| 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 5b
📆 Growing Season
75 days in Morgan County
Growing Tips for Komatsuna in Morgan County
Direct sow Komatsuna outdoors after June 17 in Morgan County when soil has warmed and frost danger has passed.
Common pests for Komatsuna in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
Morgan 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 Morgan County, UT?
Morgan County is in Zone 5b with an average last frost of June 17. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Morgan County, UT?
Morgan County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is June 17 and first fall frost is August 31.
Plan Your Garden with Confidence
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