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When to Plant Komatsuna in Saline County, MO

Saline County, Missouri Zone 6b May

Saline County, Missouri gardeners: here's your May plan

We've pulled the most time-sensitive tasks for Saline County, Missouri this May and put them front and centre. Tackle them in order.

Avg. last frost April 13
Avg. first frost October 24
Soil temp (4") 61°F
Watering Moderate
Pest pressure Low
Daylight 14.1 hrs
  1. Start komatsuna under lights

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Collect komatsuna at their peak

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

June will be here before you know it — start on
  • First harvests: komatsuna

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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.

Saline County, Missouri is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 24, giving you a growing season of approximately 194 days.

At an elevation of 1,385 feet, Saline County receives approximately 33.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Komatsuna during the growing season.

Saline County, MO (Zone 6b) Moderate season
194 days
Last Spring Frost April 13
194 growing days
First Fall Frost October 24

Saline County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (123 days to spare)
Start indoors: Mar 2 Transplant: Apr 6 🍅 Harvest: May 11 – Jun 15
Recommended (50%) ✓ Fits season (124 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 18 – Jun 22
Safe Start (90%) ✓ Fits season (119 days to spare)
Start indoors: Mar 25 Transplant: Apr 29 🍅 Harvest: Jun 3 – Jul 8

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 Saline County

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

Soil pH

Your soil pH (5.8–6.9) overlaps with Komatsuna's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Saline County is excellent for Komatsuna — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Komatsuna.

Organic Matter

Organic matter is moderate (2.8%). 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

6
successive plantings in your 194-day season

Sow every 4 weeks. Last sowing by Sep 04 to harvest before frost.

For a dedicated fall crop, sow by Aug 15.

Plant Water Budget

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

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 1.6" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 3.5" 0.8" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.3" 1" 💧 Light watering
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2.4" 1.9" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Saline 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 needs ~680 GDD — county provides 3,104 GDD Excellent fit

Komatsuna Planting Timeline — Saline County, MO

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 – Mar 23
Transplant Outdoors April 13 Apr 13 – Apr 27
Direct Sow March 30 Mar 30 – Apr 20
Harvest May 18 May 18 – Jun 22
Fall Sowing August 15 Aug 15 – Aug 29

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

194 days in Saline County

Growing Tips for Komatsuna in Saline County

Direct sow Komatsuna outdoors after April 13 in Saline County when soil has warmed and frost danger has passed.

Your generous 194.0-day season in Saline 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 Saline County, MO?

Saline County is in Zone 6b with an average last frost of April 13. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Saline County, MO?

Saline County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 24.

🌱

Your Saline County Garden Planner — Free

A 24-page printable planner built for Saline County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.