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When to Plant Komatsuna in Vernon Parish, LA

Vernon Parish, Louisiana Zone 9a May

This month in Vernon Parish, Louisiana

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.

Avg. last frost March 5
Avg. first frost November 16
Soil temp (4") 72°F
Watering Moderate
Pest pressure High
Daylight 13.6 hrs
  1. It's harvest week for komatsuna

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

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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.

Vernon Parish, Louisiana is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 16, giving you a growing season of approximately 256 days.

At an elevation of 481 feet, Vernon Parish receives approximately 54.2 inches of rainfall annually with predominantly loam soil. Summer highs average 97°F, so Komatsuna may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Komatsuna root diseases.

Vernon Parish, LA (Zone 9a) Long season
256 days
Last Spring Frost March 5
256 growing days
First Fall Frost November 16

Vernon Parish Soil Profile

Soil Type

Loam

Soil pH

6.1-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (192 days to spare)
Start indoors: Jan 25 Transplant: Feb 22 🍅 Harvest: Mar 29 – May 3
Recommended (50%) ✓ Fits season (186 days to spare)
Start indoors: Feb 5 Transplant: Mar 5 🍅 Harvest: Apr 9 – May 14
Safe Start (90%) ✓ Fits season (182 days to spare)
Start indoors: Mar 9 Transplant: Apr 6 🍅 Harvest: May 11 – Jun 15

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 Vernon Parish

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

Soil pH

Your soil pH (6.1–7.2) is within Komatsuna's preferred range (6.0–7.5).

Soil Texture

The loam soil in Vernon Parish is excellent for Komatsuna — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Komatsuna.

Organic Matter

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

How to Plant Komatsuna

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Komatsuna

8
successive plantings in your 256-day season

Sow every 4 weeks. Last sowing by Sep 27 to harvest before frost.

For a dedicated fall crop, sow by Sep 21.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 936 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 4.6" 0" ❄️ Dormant
Feb 4.7" 0" ❄️ Dormant
Mar 4.3" 5.4" 0" ✅ Rainfall sufficient
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 5.8" 0" ✅ Rainfall sufficient
Aug 4.3" 5.1" 0" ✅ Rainfall sufficient
Sep 4.3" 4.1" 0.2" 💧 Light watering
Oct 4.3" 3.8" 0.5" 💧 Light watering
Nov 4.3" 4.3" 0" ✅ Rainfall sufficient
Dec 4.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Vernon Parish). 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 needs ~967 GDD — county provides 5,824 GDD Excellent fit

Komatsuna Planting Timeline — Vernon Parish, LA

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors February 5 Feb 5 – Feb 19
Transplant Outdoors March 5 Mar 5 – Mar 19
Direct Sow February 12 Feb 12 – Mar 5
Harvest April 9 Apr 9 – May 14
Fall Sowing September 21 Sep 21 – Oct 5

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors Direct Sow
March Transplant Outdoors Direct Sow
April Harvest
May Harvest
June
July
August
September Fall Sowing
October Fall Sowing
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: ideal

🗺️ USDA Zone

Zone 9a

📆 Growing Season

256 days in Vernon Parish

Growing Tips for Komatsuna in Vernon Parish

Direct sow Komatsuna outdoors after March 05 in Vernon Parish when soil has warmed and frost danger has passed.

With summer highs reaching 97°F in Vernon Parish, provide afternoon shade for Komatsuna and water deeply in the morning.

Your generous 256.0-day season in Vernon Parish 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 Vernon Parish, LA?

Vernon Parish is in Zone 9a with an average last frost of March 5. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Vernon Parish, LA?

Vernon Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 16.

🌱

Your Vernon Parish Garden Planner — Free

A 24-page printable planner built for Vernon Parish (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Vernon Parish, LA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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