Blog

When to Plant Komatsuna in Daggett 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.

Daggett County, Utah is in USDA Zone 4b. The average last spring frost is May 13 and the first fall frost is October 1, giving you a growing season of approximately 141 days.

At an elevation of 7,540 feet, Daggett County receives approximately 14.6 inches of rainfall annually with predominantly loam soil. Summer highs average 82ยฐF, 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.

Daggett County, UT (Zone 4b) Short season
141 days
Last Spring Frost May 13
141 growing days
First Fall Frost October 1

Daggett County Soil Profile

Soil Type

Loam

Soil pH

6.8-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (70 days to spare)
Start indoors: Mar 23 Transplant: May 4 🍅 Harvest: Jun 8 – Jul 13
Recommended (50%) ✓ Fits season (71 days to spare)
Start indoors: Apr 1 Transplant: May 13 🍅 Harvest: Jun 17 – Jul 22
Safe Start (90%) ✓ Fits season (61 days to spare)
Start indoors: Apr 29 Transplant: Jun 10 🍅 Harvest: Jul 15 – Aug 19

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 851 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Komatsuna needs ~489 GDD — county provides 1,621 GDD Excellent fit

Komatsuna Planting Timeline โ€” Daggett County, UT

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors April 1 Apr 1 โ€“ Apr 15
Transplant Outdoors May 13 May 13 โ€“ May 27
Direct Sow May 6 May 6 โ€“ May 27
Fall Sowing July 9 Jul 9 โ€“ Jul 23
Harvest June 17 Jun 17 โ€“ Jul 22

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

35โ€“50 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 4b

Growing Season

141 days

Growing Tips for Daggett County

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

  • Strawberries

Level Up Your Garden

Frequently Asked Questions

When should I plant Komatsuna in Daggett County, UT?

Daggett County is in Zone 4b with an average last frost of May 13. Plan your Komatsuna planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Daggett County, UT?

Daggett County, Utah is in USDA Hardiness Zone 4b. The average last spring frost is May 13 and first fall frost is October 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Daggett County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Daggett County, UT. Local conditions may vary. Last updated: April 2026.