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When to Plant Komatsuna in Mobile County, AL

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.

Mobile County, Alabama is in USDA Zone 8b. The average last spring frost is March 3 and the first fall frost is November 24, giving you a growing season of approximately 266 days.

At an elevation of 101 feet, Mobile County receives approximately 48.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 97ยฐF, so Komatsuna may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Komatsuna will need more frequent watering and organic matter to retain nutrients.

Mobile County, AL (Zone 8b) Long season
266 days
Last Spring Frost March 3
266 growing days
First Fall Frost November 24

Mobile County Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (201 days to spare)
Start indoors: Jan 15 Transplant: Feb 19 🍅 Harvest: Mar 26 – Apr 30
Recommended (50%) ✓ Fits season (196 days to spare)
Start indoors: Jan 27 Transplant: Mar 3 🍅 Harvest: Apr 7 – May 12
Safe Start (90%) ✓ Fits season (196 days to spare)
Start indoors: Feb 13 Transplant: Mar 20 🍅 Harvest: Apr 24 – May 29

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 Mobile County

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

Soil pH

Your soil pH (4.8โ€“6.1) is more acidic than Komatsuna prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Mobile County warms quickly in spring but drains fast. Komatsuna will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Komatsuna.

Organic Matter

Organic matter is moderate (2.2%). 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

9
successive plantings in your 266-day season

Sow every 4 weeks. Last sowing by Oct 05 to harvest before frost.

For a dedicated fall crop, sow by Sep 15.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 โ€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 3.5" 0" โ„๏ธ Dormant
Mar 4.3" 4.9" 0" โœ… Rainfall sufficient
Apr 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
May 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Jun 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jul 4.3" 5.5" 0" โœ… Rainfall sufficient
Aug 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Sep 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Oct 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Nov 4.3" 4.3" 0" โœ… Rainfall sufficient
Dec โ€” 4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Mobile County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 6,051 GDD Excellent fit

Komatsuna Planting Timeline โ€” Mobile County, AL

Komatsuna Planting Calendar

Activity When Date Range
Start Indoors January 27 Jan 27 โ€“ Feb 10
Transplant Outdoors March 3 Mar 3 โ€“ Mar 17
Direct Sow February 17 Feb 17 โ€“ Mar 10
Harvest April 7 Apr 7 โ€“ May 12
Fall Sowing September 15 Sep 15 โ€“ Sep 29

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

266 days in Mobile County

Growing Tips for Komatsuna in Mobile County

Direct sow Komatsuna outdoors after March 03 in Mobile County when soil has warmed and frost danger has passed.

Sandy soil in Mobile County dries quickly โ€” mulch Komatsuna with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 97ยฐF in Mobile County, provide afternoon shade for Komatsuna and water deeply in the morning.

Your generous 266.0-day season in Mobile 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 Mobile County, AL?

Mobile County is in Zone 8b with an average last frost of March 3. Plan your Komatsuna planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Mobile County, AL?

Mobile County, Alabama is in USDA Hardiness Zone 8b. The average last spring frost is March 3 and first fall frost is November 24.

๐ŸŒฑ

Plan Your Garden with Confidence

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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 Mobile County, AL. Local conditions may vary. Last updated: April 2026.