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When to Plant Komatsuna in Teller County, CO

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.

Teller County, Colorado is in USDA Zone 5a. The average last spring frost is May 11 and the first fall frost is October 6, giving you a growing season of approximately 148 days.

At an elevation of 6,538 feet, Teller County receives approximately 19.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, 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.

Teller County, CO (Zone 5a) Short season
148 days
Last Spring Frost May 11
148 growing days
First Fall Frost October 6

Teller County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (76 days to spare)
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Jun 8 – Jul 13
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jun 15 – Jul 20
Safe Start (90%) ✓ Fits season (73 days to spare)
Start indoors: Apr 22 Transplant: May 27 🍅 Harvest: Jul 1 – Aug 5

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 Teller County

How your county's soil matches Komatsuna's growing requirements.

Soil pH

Your soil pH (6.4โ€“8.1) overlaps with Komatsuna's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Teller County is excellent for Komatsuna โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Komatsuna.

How to Plant Komatsuna

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Komatsuna

5
successive plantings in your 148-day season

Sow every 4 weeks. Last sowing by Aug 17 to harvest before frost.

For a dedicated fall crop, sow by Jul 28.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 706 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” 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 โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.2" 0" โ„๏ธ Dormant
Mar โ€” 1.9" 0" โ„๏ธ Dormant
Apr โ€” 2.1" 0" โ„๏ธ Dormant
May 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Jun 4.3" 1.3" 3" ๐Ÿšฟ Regular watering
Jul 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Aug 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Sep 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Oct 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Nov โ€” 1.3" 0" โ„๏ธ Dormant
Dec โ€” 1.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Teller County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~552 GDD — county provides 1,924 GDD Excellent fit

Komatsuna Planting Timeline โ€” Teller County, CO

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors April 6 Apr 6 โ€“ Apr 20
Transplant Outdoors May 11 May 11 โ€“ May 25
Direct Sow April 27 Apr 27 โ€“ May 18
Harvest June 15 Jun 15 โ€“ Jul 20
Fall Sowing July 28 Jul 28 โ€“ Aug 11

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 Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Fall Sowing
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

148 days in Teller County

Growing Tips for Komatsuna in Teller County

Direct sow Komatsuna outdoors after May 11 in Teller County when soil has warmed and frost danger has passed.

Your generous 148.0-day season in Teller 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.

Teller County receives only 20" of rain annually. Komatsuna needs consistent moisture โ€” 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

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Komatsuna in Teller County, CO?

Teller County is in Zone 5a with an average last frost of May 11. Plan your Komatsuna planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Teller County, CO?

Teller County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is May 11 and first fall frost is October 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Teller County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

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