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When to Plant Microgreens in Harrison County, OH

Harrison County, Ohio Zone 6b May

May in Harrison County, Ohio — your action list

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

Avg. last frost April 26
Avg. first frost October 25
Soil temp (4") 60°F
Watering Low
Pest pressure Low
Daylight 14.2 hrs
  1. Start microgreens indoors

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. Harvest microgreens as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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Microgreens are young seedlings of vegetables and herbs harvested at the cotyledon or first true leaf stage. They pack concentrated flavors and nutrients in a tiny package.

Harrison County, Ohio is in USDA Zone 6b. The average last spring frost is April 26 and the first fall frost is October 25, giving you a growing season of approximately 182 days.

At an elevation of 1,138 feet, Harrison County receives approximately 38.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Microgreens during the growing season.

Harrison County, OH (Zone 6b) Moderate season
182 days
Last Spring Frost April 26
182 growing days
First Fall Frost October 25

Harrison County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (147 days to spare)
Start indoors: Mar 15 Transplant: Apr 19 🍅 Harvest: Apr 26 – May 24
Recommended (50%) ✓ Fits season (147 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: May 3 – May 31
Safe Start (90%) ✓ Fits season (143 days to spare)
Start indoors: Apr 9 Transplant: May 14 🍅 Harvest: May 21 – Jun 18

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 Harrison County

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

Soil pH

Your soil pH (6.1–7.2) overlaps with Microgreens's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) — Microgreens will thrive.

How to Plant Microgreens

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

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

Succession Planting Microgreens

36
successive plantings in your 182-day season

Sow every 0.7 weeks. Last sowing by Oct 04 to harvest before frost.

For a dedicated fall crop, sow by Aug 16.

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 173 gal / 100 sq ft

Monthly Watering Guide for Microgreens

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

Month Microgreens Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 3" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 5.1" 0" ✅ Rainfall sufficient
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

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

Microgreens 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.

Microgreens needs ~192 GDD — county provides 2,502 GDD Excellent fit

Microgreens Planting Timeline — Harrison County, OH

Microgreens 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 12 Apr 12 – May 3
Harvest May 3 May 3 – May 31
Fall Sowing August 16 Aug 16 – Aug 30

Plant 0.5" deep · 2" apart · Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

7–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

182 days in Harrison County

Growing Tips for Microgreens in Harrison County

Direct sow Microgreens outdoors after April 26 in Harrison County when soil has warmed and frost danger has passed.

Your generous 182.0-day season in Harrison County allows multiple plantings of Microgreens. Sow every 3.0 days for continuous harvest.

General growing tips

Sow seeds densely on shallow trays of moist growing medium. Cover until germination, then provide light. Harvest with scissors when 1-3 inches tall. Grow year-round indoors.

Frequently Asked Questions

When should I plant Microgreens in Harrison County, OH?

Harrison County is in Zone 6b with an average last frost of April 26. Plan your Microgreens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Harrison County, OH?

Harrison County, Ohio is in USDA Hardiness Zone 6b. The average last spring frost is April 26 and first fall frost is October 25.

🌱

Your Harrison County Garden Planner — Free

A 24-page printable planner built for Harrison 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 Harrison 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.