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When to Plant Komatsuna in Larue County, KY

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.

Larue County, Kentucky is in USDA Zone 6b. The average last spring frost is April 4 and the first fall frost is November 1, giving you a growing season of approximately 211 days.

At an elevation of 2,923 feet, Larue County receives approximately 52.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90ยฐF, providing good warmth for Komatsuna during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Komatsuna root diseases.

Larue County, KY (Zone 6b) Long season
211 days
Last Spring Frost April 4
211 growing days
First Fall Frost November 1

Larue County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (141 days to spare)
Start indoors: Feb 22 Transplant: Mar 29 🍅 Harvest: May 3 – Jun 7
Recommended (50%) ✓ Fits season (141 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 9 – Jun 13
Safe Start (90%) ✓ Fits season (135 days to spare)
Start indoors: Mar 18 Transplant: Apr 22 🍅 Harvest: May 27 – Jul 1

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 Larue County

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

Soil pH

Your soil pH (5.4โ€“6.5) is more acidic than Komatsuna prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.2%). 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

7
successive plantings in your 211-day season

Sow every 4 weeks. Last sowing by Sep 12 to harvest before frost.

For a dedicated fall crop, sow by Aug 23.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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€” 4.1" 0" โ„๏ธ Dormant
Feb โ€” 4" 0" โ„๏ธ Dormant
Mar โ€” 5.2" 0" โ„๏ธ Dormant
Apr 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
May 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Jun 4.3" 5.3" 0" โœ… Rainfall sufficient
Jul 4.3" 5.3" 0" โœ… Rainfall sufficient
Aug 4.3" 4.8" 0" โœ… Rainfall sufficient
Sep 4.3" 4.3" 0" โœ… Rainfall sufficient
Oct 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Nov 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Dec โ€” 4.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Nov in Larue 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 ~744 GDD — county provides 3,692 GDD Excellent fit

Komatsuna Planting Timeline โ€” Larue County, KY

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 โ€“ Mar 14
Transplant Outdoors April 4 Apr 4 โ€“ Apr 18
Direct Sow March 21 Mar 21 โ€“ Apr 11
Harvest May 9 May 9 โ€“ Jun 13
Fall Sowing August 23 Aug 23 โ€“ Sep 6

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

211 days in Larue County

Growing Tips for Komatsuna in Larue County

Direct sow Komatsuna outdoors after April 04 in Larue County when soil has warmed and frost danger has passed.

Your generous 211.0-day season in Larue 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.

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 Larue County, KY?

Larue County is in Zone 6b with an average last frost of April 4. Plan your Komatsuna planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Larue County, KY?

Larue County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 4 and first fall frost is November 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Larue County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Larue County, KY. Local conditions may vary. Last updated: April 2026.