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When to plant Komatsuna in Jackson County, KS

Plant Komatsuna in Jackson County from March 31 to April 21 in spring. Jackson County sits in USDA Zone 6a, with last frost around April 14 and first frost on October 22. A second sowing from August 13 to August 27 extends the harvest into fall.

When to Plant Komatsuna in Jackson County, KS

Jackson County, Kansas Zone 6a June

Top priorities for Jackson County, Kansas gardeners in June

Your garden in Jackson County, Kansas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 14
Avg. first frost October 22
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Collect komatsuna at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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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.

Jackson County, Kansas is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 22, giving you a growing season of approximately 191 days.

At an elevation of 909 feet, Jackson County receives approximately 25.8 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Komatsuna during the growing season.

Jackson County, KS (Zone 6a) Moderate season
191 days
Last Spring Frost April 14
191 growing days
First Fall Frost October 22

Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

Komatsuna Planting Risk Windows

Early Start (70% safe) ✓ Fits season (118 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: May 14 – Jun 18
Recommended (50%) ✓ Fits season (121 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: May 19 – Jun 23
Safe Start (90%) ✓ Fits season (123 days to spare)
Start indoors: Mar 26 Transplant: Apr 30 🍅 Harvest: Jun 4 – Jul 9

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 Jackson County

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

Soil pH

Your soil pH (6.8–7.8) overlaps with Komatsuna's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Komatsuna.

Organic Matter

Organic matter is excellent (4.1%) — Komatsuna will thrive.

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 191-day season

Sow every 4 weeks. Last sowing by Sep 02 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Komatsuna Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,495 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 0.7" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 4.3" 2.4" 1.9" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.1" 2.2" 🚿 Regular watering
Oct 4.3" 1.6" 2.7" 🚿 Regular watering
Nov 0.9" 0" ❄️ Dormant
Dec 0.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jackson 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 ~584 GDD — county provides 2,626 GDD Excellent fit

Komatsuna Planting Timeline — Jackson County, KS

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 – Mar 24
Transplant Outdoors April 14 Apr 14 – Apr 28
Direct Sow March 31 Mar 31 – Apr 21
Harvest May 19 May 19 – Jun 23
Fall Sowing August 13 Aug 13 – Aug 27

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 · 2-3 times/week

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

191 days in Jackson County

Growing Tips for Komatsuna in Jackson County

Direct sow Komatsuna outdoors after April 14 in Jackson County when soil has warmed and frost danger has passed.

Your generous 191.0-day season in Jackson 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 Jackson County, KS?

Jackson County is in Zone 6a with an average last frost of April 14. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, KS?

Jackson County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 22.

When should I plant Komatsuna in Jackson County, KS?

In Jackson County, KS, plant Komatsuna after the last frost (around April 14) and before the first frost (around October 22). Best results when soil holds above 50°F.

What growing zone is Jackson County, KS for Komatsuna?

Jackson County sits in USDA Zone 6a. Komatsuna grows reliably in zones 2a through 11b, so it's a good fit here.

Can Komatsuna grow in Jackson County's climate?

Yes — Komatsuna grows well in Jackson County's temperate climate. Jackson County averages a 191-day frost-free season, with last frost around April 14 and first frost around October 22.

🌱

Your Jackson County Garden Planner — Free

A 22-page printable planner built for Jackson County (Zone 6a). 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 Jackson County, KS. Local conditions may vary. Last updated: June 2026.

Sources & credits

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