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When to plant Mitsuba in St. Clair County, IL

St. Clair County's spring Mitsuba window runs March 19 through April 9. most warm-season crops establish quickly once soil holds above 60°F. A second sowing from August 24 to September 7 extends the harvest into fall.

When to Plant Mitsuba in St. Clair County, IL

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.

St. Clair County, Illinois is in USDA Zone 7a. The average last spring frost is April 2 and the first fall frost is November 2, giving you a growing season of approximately 214 days.

At an elevation of 711 feet, St. Clair County receives approximately 34.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Mitsuba during the growing season.

St. Clair County, IL (Zone 7a) Long season
214 days
Last Spring Frost April 2
214 growing days
First Fall Frost November 2

St. Clair County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 4.3" 2.4" 1.9" 💧 Light watering
Dec 1.8" 0" ❄️ Dormant

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

Mitsuba Planting Timeline — St. Clair County, IL

Mitsuba Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors March 26 Mar 26 – Apr 9
Direct Sow March 19 Mar 19 – Apr 9
Harvest May 21 May 21 – Jul 16
Fall Sowing August 24 Aug 24 – Sep 7

Plant 0.5" deep · 8" 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
May Harvest
June Harvest
July Harvest
August Fall Sowing
September Fall Sowing
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

214 days in St. Clair County

Growing Tips for St. Clair County

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 St. Clair County, IL?

St. Clair County is in Zone 7a with an average last frost of April 2. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Clair County, IL?

St. Clair County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 2 and first fall frost is November 2.

When should I plant Mitsuba in St. Clair County, IL?

In St. Clair County, IL, plant Mitsuba after the last frost (around April 2) and before the first frost (around November 2). Best results when soil holds above 50°F.

What growing zone is St. Clair County, IL for Mitsuba?

St. Clair County sits in USDA Zone 7a. Mitsuba grows reliably in zones 4a through 9b, so it's a good fit here.

Can Mitsuba grow in St. Clair County's climate?

Yes — Mitsuba grows well in St. Clair County's temperate climate. St. Clair County averages a 214-day frost-free season, with last frost around April 2 and first frost around November 2.

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Your St. Clair County Garden Planner — Free

A 22-page printable planner built for St. Clair County (Zone 7a). 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 St. Clair County, IL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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