When to Plant Komatsuna in Sanpete County, UT
Your May game plan for Sanpete County, Utah
Here's what deserves your attention in Sanpete County, Utah this month. Everything below is tailored to Zone 6a and timed around your local frost dates.
-
Harden off and plant komatsuna
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
-
Direct-sow komatsuna
Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.
Get ahead of June
- 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.
Sanpete County, Utah is in USDA Zone 6a. The average last spring frost is May 21 and the first fall frost is September 28, giving you a growing season of approximately 130 days.
At an elevation of 6,969 feet, Sanpete County receives approximately 14.2 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Komatsuna during the growing season. With low rainfall, drip irrigation is essential for growing Komatsuna successfully. Mulch heavily to conserve soil moisture.
Sanpete 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 Sanpete 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 Sanpete County is excellent for Komatsuna — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.2%). 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 09 to harvest before frost.
For a dedicated fall crop, sow by Jul 20.
Plant Water Budget
Water stress score is 6/10 — 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" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | — | 1.5" | 0" | ❄️ Dormant |
| May | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jun | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Jul | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Aug | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Sep | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Oct | — | 1.1" | 0" | ❄️ Dormant |
| Nov | — | 0.9" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Sanpete 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 — Sanpete 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 20 | Jul 20 – Aug 3 |
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
130 days in Sanpete County
Growing Tips for Komatsuna in Sanpete County
Direct sow Komatsuna outdoors after May 21 in Sanpete County when soil has warmed and frost danger has passed.
Your generous 130.0-day season in Sanpete 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.
Sanpete 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 Sanpete County, UT?
Sanpete 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 Sanpete County, UT?
Sanpete County, Utah is in USDA Hardiness Zone 6a. The average last spring frost is May 21 and first fall frost is September 28.
Your Sanpete County Garden Planner — Free
A 24-page printable planner built for Sanpete 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.