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When to Plant Komatsuna in Rowan County, NC

Rowan County, North Carolina Zone 7b May

May in Rowan County, North Carolina — your action list

Here's what deserves your attention in Rowan County, North Carolina this month. Everything below is tailored to Zone 7b and timed around your local frost dates.

Avg. last frost March 30
Avg. first frost November 3
Soil temp (4") 68°F
Watering Moderate
Pest pressure Moderate
Daylight 13.9 hrs
  1. Indoor seed-starting week for komatsuna

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

  2. Collect komatsuna at their peak

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Coming up in June — start thinking about
  • 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.

Rowan County, North Carolina is in USDA Zone 7b. The average last spring frost is March 30 and the first fall frost is November 3, giving you a growing season of approximately 218 days.

At an elevation of 179 feet, Rowan County receives approximately 46.7 inches of rainfall annually with predominantly clay loam soil. Summer highs average 92°F, providing good warmth for Komatsuna during the growing season. Clay soil retains moisture well for Komatsuna, but amend with compost to improve drainage and prevent root rot.

Rowan County, NC (Zone 7b) Long season
218 days
Last Spring Frost March 30
218 growing days
First Fall Frost November 3

Rowan County Soil Profile

Soil Type

Clay Loam

Soil pH

5.7-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Start indoors: Feb 15 Transplant: Mar 22 🍅 Harvest: Apr 26 – May 31
Recommended (50%) ✓ Fits season (148 days to spare)
Start indoors: Feb 23 Transplant: Mar 30 🍅 Harvest: May 4 – Jun 8
Safe Start (90%) ✓ Fits season (144 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: May 21 – Jun 25

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 Rowan County

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

Soil pH

Your soil pH (5.7–6.4) overlaps with Komatsuna's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.4%). 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 218-day season

Sow every 4 weeks. Last sowing by Sep 14 to harvest before frost.

For a dedicated fall crop, sow by Aug 25.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 195 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 4.2" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 4.3" 4.6" 0" ✅ Rainfall sufficient
Apr 4.3" 3.5" 0.8" 💧 Light watering
May 4.3" 3.4" 0.9" 💧 Light watering
Jun 4.3" 3.5" 0.8" 💧 Light watering
Jul 4.3" 4.9" 0" ✅ Rainfall sufficient
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 4.3" 3.4" 0.9" 💧 Light watering
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Rowan 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 ~808 GDD — county provides 4,142 GDD Excellent fit

Komatsuna Planting Timeline — Rowan County, NC

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 16 Mar 16 – Apr 6
Harvest May 4 May 4 – Jun 8
Fall Sowing August 25 Aug 25 – Sep 8

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

218 days in Rowan County

Growing Tips for Komatsuna in Rowan County

Direct sow Komatsuna outdoors after March 30 in Rowan County when soil has warmed and frost danger has passed.

With Rowan County's clay soil (31% clay), work in 3-4 inches of compost before planting Komatsuna. Avoid tilling when soil is wet to prevent compaction.

Your generous 218.0-day season in Rowan 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 Rowan County, NC?

Rowan County is in Zone 7b with an average last frost of March 30. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Rowan County, NC?

Rowan County, North Carolina is in USDA Hardiness Zone 7b. The average last spring frost is March 30 and first fall frost is November 3.

🌱

Your Rowan County Garden Planner — Free

A 24-page printable planner built for Rowan County (Zone 7b). 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 Rowan County, NC. 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.