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When to Plant Mitsuba in Caswell County, NC

Caswell County, North Carolina Zone 7b May

What to do in May

Your garden in Caswell County, North Carolina is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost April 6
Avg. first frost October 31
Soil temp (4") 66°F
Watering Moderate
Pest pressure Moderate
Daylight 13.9 hrs
  1. Fire up the seed-starting tray: mitsuba

    These need a head start before your last frost (April 6). Sow into cells now so you're ready to transplant in a few weeks.

  2. Collect mitsuba at their peak

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Coming up in June — start thinking about
  • First harvests: mitsuba

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Mitsuba (Japanese parsley) is a shade-loving herb with trefoil leaves and a mild celery-parsley flavor. It is essential in Japanese cuisine for soups, salads, and garnishes.

Caswell County, North Carolina is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.

At an elevation of 608 feet, Caswell County receives approximately 42.7 inches of rainfall annually with predominantly clay loam soil. Summer highs average 94°F, providing good warmth for Mitsuba during the growing season. Clay soil retains moisture well for Mitsuba, but amend with compost to improve drainage and prevent root rot.

Caswell County, NC (Zone 7b) Long season
208 days
Last Spring Frost April 6
208 growing days
First Fall Frost October 31

Caswell County Soil Profile

Soil Type

Clay Loam

Soil pH

5.7-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (106 days to spare)
Start indoors: Feb 21 Transplant: Mar 21 🍅 Harvest: May 16 – Jul 11
Recommended (50%) ✓ Fits season (103 days to spare)
Start indoors: Mar 2 Transplant: Mar 30 🍅 Harvest: May 25 – Jul 20
Safe Start (90%) ✓ Fits season (99 days to spare)
Start indoors: Mar 19 Transplant: Apr 16 🍅 Harvest: Jun 11 – Aug 6

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 Caswell County

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

Soil pH

Your soil pH (5.7–6.2) is more acidic than Mitsuba prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Mitsuba.

How to Plant Mitsuba

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Mitsuba

4
successive plantings in your 208-day season

Sow every 5.7 weeks. Last sowing by Aug 22 to harvest before frost.

For a dedicated fall crop, sow by Aug 22.

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 255 gal / 100 sq ft

Monthly Watering Guide for Mitsuba

Mitsuba needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Mitsuba Needs Rainfall You Supplement Action
Jan 3.9" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 3.9" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3" 1.3" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 4.8" 0" ✅ Rainfall sufficient
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 3.3" 0" ❄️ Dormant
Dec 3.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Caswell County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Mitsuba 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.

Mitsuba needs ~1,230 GDD — county provides 4,264 GDD Excellent fit

Mitsuba Planting Timeline — Caswell County, NC

Mitsuba Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 – Mar 16
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 23 Mar 23 – Apr 13
Harvest May 25 May 25 – Jul 20
Fall Sowing August 22 Aug 22 – Sep 5

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
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

50–70 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7b

📆 Growing Season

208 days in Caswell County

Growing Tips for Mitsuba in Caswell County

Direct sow Mitsuba outdoors after April 06 in Caswell County when soil has warmed and frost danger has passed.

With Caswell County's clay soil (34% clay), work in 3-4 inches of compost before planting Mitsuba. Avoid tilling when soil is wet to prevent compaction.

Common pests for Mitsuba in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow or start indoors in partial shade. Mitsuba prefers cool, moist conditions. Harvest outer stems as needed. Self-sows readily in shaded garden areas.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mitsuba in Caswell County, NC?

Caswell County is in Zone 7b with an average last frost of April 6. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.

What planting zone is Caswell County, NC?

Caswell County, North Carolina is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 31.

🌱

Your Caswell County Garden Planner — Free

A 24-page printable planner built for Caswell 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 Caswell County, NC. Local conditions may vary. Last updated: May 2026.

Sources & credits

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