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When to plant Mitsuba in Olmsted County, MN

For Mitsuba in Olmsted County, the safe spring window opens around April 26 and closes around May 17. Last expected frost is May 3, first fall frost October 4, giving a 154-day growing season. A second sowing from July 12 to July 26 extends the harvest into fall.

When to Plant Mitsuba in Olmsted County, MN

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.

Olmsted County, Minnesota is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 4, giving you a growing season of approximately 154 days.

At an elevation of 992 feet, Olmsted County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Mitsuba to ensure they mature before fall.

Olmsted County, MN (Zone 4b) Moderate season
154 days
Last Spring Frost May 3
154 growing days
First Fall Frost October 4

Olmsted County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

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 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 2.9" 0" ❄️ Dormant
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.4" 1.9" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Mitsuba Planting Timeline — Olmsted County, MN

Mitsuba Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 26 Apr 26 – May 17
Harvest June 21 Jun 21 – Aug 16
Fall Sowing July 12 Jul 12 – Jul 26

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Harvest
September
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 4b

📆 Growing Season

154 days in Olmsted County

Growing Tips for Olmsted 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 Olmsted County, MN?

Olmsted County is in Zone 4b with an average last frost of May 3. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.

What planting zone is Olmsted County, MN?

Olmsted County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 4.

When should I plant Mitsuba in Olmsted County, MN?

In Olmsted County, MN, plant Mitsuba after the last frost (around May 3) and before the first frost (around October 4). Best results when soil holds above 50°F.

What growing zone is Olmsted County, MN for Mitsuba?

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

Can Mitsuba grow in Olmsted County's climate?

Yes — Mitsuba grows well in Olmsted County's temperate climate. Olmsted County averages a 154-day frost-free season, with last frost around May 3 and first frost around October 4.

🌱

Your Olmsted County Garden Planner — Free

A 22-page printable planner built for Olmsted County (Zone 4b). 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 Olmsted County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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