When to Plant Komatsuna in Beaver County, UT
What to do in May
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Transplant komatsuna outside
Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.
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Scatter komatsuna into prepared beds
Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.
June will be here before you know it — start on
- 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.
Beaver County, Utah is in USDA Zone 6a. The average last spring frost is May 21 and the first fall frost is September 29, giving you a growing season of approximately 131 days.
At an elevation of 7,589 feet, Beaver County receives approximately 24.3 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Komatsuna during the growing season.
Beaver County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
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 Beaver County
How your county's soil matches Komatsuna's growing requirements.
Soil pH
Your soil pH (6.5–7.8) overlaps with Komatsuna's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Beaver 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 (2.8%). 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 10 to harvest before frost.
For a dedicated fall crop, sow by Jul 21.
Plant Water Budget
Water stress score is 10/10 — 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | — | 2.3" | 0" | ❄️ Dormant |
| May | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Jun | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Jul | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Aug | 4.3" | 2.3" | 2" | 💧 Light watering |
| Sep | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Oct | — | 2.3" | 0" | ❄️ Dormant |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Beaver 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 — Beaver County, UT
Komatsuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 16 | Apr 16 – Apr 30 |
| Transplant Outdoors | May 21 | May 21 – Jun 4 |
| Direct Sow | May 7 | May 7 – May 28 |
| Harvest | June 25 | Jun 25 – Jul 30 |
| 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 · 1-2 times/week
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
131 days in Beaver County
Growing Tips for Komatsuna in Beaver County
Direct sow Komatsuna outdoors after May 21 in Beaver County when soil has warmed and frost danger has passed.
Your generous 131.0-day season in Beaver 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.
Beaver County receives only 24" 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 Beaver County, UT?
Beaver County is in Zone 6a with an average last frost of May 21. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Beaver County, UT?
Beaver County, Utah is in USDA Hardiness Zone 6a. The average last spring frost is May 21 and first fall frost is September 29.
Your Beaver County Garden Planner — Free
A 24-page printable planner built for Beaver County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.