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When to Plant Mitsuba in Macoupin County, IL

Macoupin County, Illinois Zone 6b May

May in the garden — Macoupin County, Illinois

Each item below is timed to Macoupin County, Illinois's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 11
Avg. first frost October 21
Soil temp (4") 64°F
Watering Low
Pest pressure Low
Daylight 14.2 hrs
  1. Sow mitsuba in trays indoors

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. Bring in the mitsuba

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Get ahead of June
  • 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.

Macoupin County, Illinois is in USDA Zone 6b. The average last spring frost is April 11 and the first fall frost is October 21, giving you a growing season of approximately 193 days.

At an elevation of 859 feet, Macoupin County receives approximately 30.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Mitsuba during the growing season.

Macoupin County, IL (Zone 6b) Moderate season
193 days
Last Spring Frost April 11
193 growing days
First Fall Frost October 21

Macoupin County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (90 days to spare)
Start indoors: Feb 28 Transplant: Mar 28 🍅 Harvest: May 23 – Jul 18
Recommended (50%) ✓ Fits season (88 days to spare)
Start indoors: Mar 7 Transplant: Apr 4 🍅 Harvest: May 30 – Jul 25
Safe Start (90%) ✓ Fits season (93 days to spare)
Start indoors: Mar 16 Transplant: Apr 13 🍅 Harvest: Jun 8 – Aug 3

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 Macoupin County

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

Soil pH

Your soil pH (6.0–7.2) overlaps with Mitsuba's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.0%) — Mitsuba will thrive.

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 193-day season

Sow every 5.7 weeks. Last sowing by Aug 12 to harvest before frost.

For a dedicated fall crop, sow by Aug 12.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 563 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 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 2.7" 1.6" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 3" 1.3" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.1" 2.2" 🚿 Regular watering
Nov 2" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Macoupin 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 ~1,050 GDD — county provides 3,377 GDD Excellent fit

Mitsuba Planting Timeline — Macoupin County, IL

Mitsuba Planting Calendar

Activity When Date Range
Start Indoors March 7 Mar 7 – Mar 21
Transplant Outdoors April 4 Apr 4 – Apr 18
Direct Sow March 28 Mar 28 – Apr 18
Harvest May 30 May 30 – Jul 25
Fall Sowing August 12 Aug 12 – Aug 26

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

193 days in Macoupin County

Growing Tips for Mitsuba in Macoupin County

Direct sow Mitsuba outdoors after April 11 in Macoupin County when soil has warmed and frost danger has passed.

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 Macoupin County, IL?

Macoupin County is in Zone 6b with an average last frost of April 11. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.

What planting zone is Macoupin County, IL?

Macoupin County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 11 and first fall frost is October 21.

🌱

Your Macoupin County Garden Planner — Free

A 24-page printable planner built for Macoupin County (Zone 6b). 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 Macoupin County, IL. 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.