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When to Plant Komatsuna in Bryan County, OK

Bryan County, Oklahoma Zone 8a May

Top priorities for Bryan County, Oklahoma gardeners in May

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Bryan County, Oklahoma.

Avg. last frost March 25
Avg. first frost November 11
Soil temp (4") 67°F
Watering Moderate
Pest pressure Moderate
Daylight 13.8 hrs
  1. Bring in the komatsuna

    If you can't use it all right away, check the food-preservation section of your planner.

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.

Bryan County, Oklahoma is in USDA Zone 8a. The average last spring frost is March 25 and the first fall frost is November 11, giving you a growing season of approximately 231 days.

At an elevation of 928 feet, Bryan County receives approximately 22.3 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Komatsuna during the growing season.

Bryan County, OK (Zone 8a) Long season
231 days
Last Spring Frost March 25
231 growing days
First Fall Frost November 11

Bryan County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (166 days to spare)
Start indoors: Feb 4 Transplant: Mar 11 🍅 Harvest: Apr 15 – May 20
Recommended (50%) ✓ Fits season (161 days to spare)
Start indoors: Feb 18 Transplant: Mar 25 🍅 Harvest: Apr 29 – Jun 3
Safe Start (90%) ✓ Fits season (159 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 20 – Jun 24

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 Bryan County

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

Soil pH

Your soil pH (6.2–7.1) is within Komatsuna's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is moderate (3.7%). 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

8
successive plantings in your 231-day season

Sow every 4 weeks. Last sowing by Sep 22 to harvest before frost.

For a dedicated fall crop, sow by Sep 02.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 1,467 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 0.5" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 4.3" 1.6" 2.7" 🚿 Regular watering
Apr 4.3" 2.3" 2" 💧 Light watering
May 4.3" 3" 1.3" 💧 Light watering
Jun 4.3" 3.6" 0.7" 💧 Light watering
Jul 4.3" 2.8" 1.5" 💧 Light watering
Aug 4.3" 2.6" 1.7" 💧 Light watering
Sep 4.3" 2.4" 1.9" 💧 Light watering
Oct 4.3" 1.5" 2.8" 🚿 Regular watering
Nov 4.3" 0.8" 3.5" 🚿 Regular watering
Dec 0.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Bryan 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 ~744 GDD — county provides 4,042 GDD Excellent fit

Komatsuna Planting Timeline — Bryan County, OK

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors March 25 Mar 25 – Apr 8
Direct Sow March 11 Mar 11 – Apr 1
Harvest April 29 Apr 29 – Jun 3
Fall Sowing September 2 Sep 2 – Sep 16

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 Harvest
May Harvest
June Harvest
July
August
September Fall Sowing
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: ideal

🗺️ USDA Zone

Zone 8a

📆 Growing Season

231 days in Bryan County

Growing Tips for Komatsuna in Bryan County

Direct sow Komatsuna outdoors after March 25 in Bryan County when soil has warmed and frost danger has passed.

Your generous 231.0-day season in Bryan 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.

Bryan County receives only 22" of rain annually. Komatsuna needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Bryan County, OK?

Bryan County is in Zone 8a with an average last frost of March 25. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Bryan County, OK?

Bryan County, Oklahoma is in USDA Hardiness Zone 8a. The average last spring frost is March 25 and first fall frost is November 11.

🌱

Your Bryan County Garden Planner — Free

A 24-page printable planner built for Bryan County (Zone 8a). 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 Bryan County, OK. 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.