When to Plant Komatsuna in Chatham County, NC
May in Chatham County, North Carolina — your action list
Here's what deserves your attention in Chatham County, North Carolina this month. Everything below is tailored to Zone 8a and timed around your local frost dates.
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Start komatsuna under lights
These need a head start before your last frost (March 28). Sow into cells now so you're ready to transplant in a few weeks.
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Harvest komatsuna as they ripen
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Coming up in June — start thinking about
- First harvests: komatsuna
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.
Chatham County, North Carolina is in USDA Zone 8a. The average last spring frost is March 28 and the first fall frost is November 6, giving you a growing season of approximately 223 days.
At an elevation of 1,042 feet, Chatham County receives approximately 48.2 inches of rainfall annually with predominantly clay loam soil. Summer highs average 90°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.
Chatham County Soil Profile
Soil Type
Clay Loam
Soil pH
5.5-6.4
Drainage
Well Drained
Plant Planting Risk Windows
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 Chatham County
How your county's soil matches Komatsuna's growing requirements.
Soil pH
Your soil pH (5.5–6.4) is more acidic than Komatsuna prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The clay loam soil in Chatham County is excellent for Komatsuna — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Komatsuna.
How to Plant Komatsuna
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Komatsuna
Sow every 4 weeks. Last sowing by Sep 17 to harvest before frost.
For a dedicated fall crop, sow by Aug 28.
Plant Water Budget
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 | — | 3.7" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| May | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jun | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Oct | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Nov | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Dec | — | 3.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Chatham 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 Planting Timeline — Chatham County, NC
Komatsuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 21 | Feb 21 – Mar 7 |
| Transplant Outdoors | March 28 | Mar 28 – Apr 11 |
| Direct Sow | March 14 | Mar 14 – Apr 4 |
| Harvest | May 2 | May 2 – Jun 6 |
| Fall Sowing | August 28 | Aug 28 – Sep 11 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| 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: too_acidic
🗺️ USDA Zone
Zone 8a
📆 Growing Season
223 days in Chatham County
Growing Tips for Komatsuna in Chatham County
Direct sow Komatsuna outdoors after March 28 in Chatham County when soil has warmed and frost danger has passed.
With Chatham County's clay soil (28% clay), work in 3-4 inches of compost before planting Komatsuna. Avoid tilling when soil is wet to prevent compaction.
Your generous 223.0-day season in Chatham 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
Check more plant combinations with our Companion Planting Checker →
Komatsuna in Other Locations
Frequently Asked Questions
When should I plant Komatsuna in Chatham County, NC?
Chatham County is in Zone 8a with an average last frost of March 28. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Chatham County, NC?
Chatham County, North Carolina is in USDA Hardiness Zone 8a. The average last spring frost is March 28 and first fall frost is November 6.
Your Chatham County Garden Planner — Free
A 24-page printable planner built for Chatham 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.