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When to Plant Mizuna in Portage County, OH

Portage County, Ohio Zone 6a May

May in the garden — Portage County, Ohio

Here's what deserves your attention in Portage County, Ohio this month. Everything below is tailored to Zone 6a and timed around your local frost dates.

Avg. last frost May 4
Avg. first frost October 13
Soil temp (4") 57°F
Watering Low
Pest pressure Low
Daylight 14.3 hrs
  1. Move mizuna from tray to bed

    Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.

Coming up in June — start thinking about
  • Starting indoors: mizuna
  • First harvests: mizuna

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Mizuna is a mild-flavored Japanese mustard green with feathery, deeply serrated leaves. It is fast-growing and makes an excellent addition to salads and stir-fries.

Portage County, Ohio is in USDA Zone 6a. The average last spring frost is May 4 and the first fall frost is October 13, giving you a growing season of approximately 162 days.

At an elevation of 1,164 feet, Portage County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Mizuna during the growing season.

Portage County, OH (Zone 6a) Moderate season
162 days
Last Spring Frost May 4
162 growing days
First Fall Frost October 13

Portage County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (100 days to spare)
Start indoors: Mar 24 Transplant: Apr 28 🍅 Harvest: Jun 2 – Jun 30
Recommended (50%) ✓ Fits season (99 days to spare)
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Jun 8 – Jul 6
Safe Start (90%) ✓ Fits season (94 days to spare)
Start indoors: Apr 17 Transplant: May 22 🍅 Harvest: Jun 26 – Jul 24

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 Portage County

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

Soil pH

Your soil pH (6.2–6.8) is within Mizuna's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — Mizuna will thrive.

How to Plant Mizuna

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Mizuna

6
successive plantings in your 162-day season

Sow every 3.4 weeks. Last sowing by Aug 29 to harvest before frost.

For a dedicated fall crop, sow by Aug 04.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Mizuna

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

Month Mizuna Needs Rainfall You Supplement Action
Jan 1.9" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.6" 0" ❄️ Dormant
May 4.3" 4.7" 0" ✅ Rainfall sufficient
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 4.9" 0" ✅ Rainfall sufficient
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

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

Mizuna 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.

Mizuna needs ~516 GDD — county provides 2,227 GDD Excellent fit

Mizuna Planting Timeline — Portage County, OH

Mizuna Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 4 May 4 – May 18
Direct Sow April 20 Apr 20 – May 11
Harvest June 8 Jun 8 – Jul 6
Fall Sowing August 4 Aug 4 – Aug 18

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

30–45 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

162 days in Portage County

Growing Tips for Mizuna in Portage County

Direct sow Mizuna outdoors after May 04 in Portage County when soil has warmed and frost danger has passed.

Your generous 162.0-day season in Portage County allows multiple plantings of Mizuna. Sow every 15.0 days for continuous harvest.

Common pests for Mizuna 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. Harvest outer leaves as needed for a cut-and-come-again approach. Mizuna is one of the most cold-tolerant Asian greens.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mizuna in Portage County, OH?

Portage County is in Zone 6a with an average last frost of May 4. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Portage County, OH?

Portage County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is May 4 and first fall frost is October 13.

🌱

Your Portage County Garden Planner — Free

A 24-page printable planner built for Portage County (Zone 6a). 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 Portage County, OH. 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.