Blog

When to Plant Microgreens in Johnson County, KY

Johnson County, Kentucky Zone 7a May

Johnson County, Kentucky gardeners: here's your May plan

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Johnson County, Kentucky.

Avg. last frost April 14
Avg. first frost October 26
Soil temp (4") 54°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs
  1. Begin indoor sowing: microgreens

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Harvest microgreens as they ripen

    If you can't use it all right away, check the food-preservation section of your planner.

Instant PDF download. No spam, unsubscribe any time.

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.

Johnson County, Kentucky is in USDA Zone 7a. The average last spring frost is April 14 and the first fall frost is October 26, giving you a growing season of approximately 195 days.

At an elevation of 3,308 feet, Johnson County receives approximately 47 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Microgreens during the growing season.

Johnson County, KY (Zone 7a) Moderate season
195 days
Last Spring Frost April 14
195 growing days
First Fall Frost October 26

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (161 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: Apr 15 – May 13
Recommended (50%) ✓ Fits season (160 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Apr 21 – May 19
Safe Start (90%) ✓ Fits season (157 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: May 9 – Jun 6

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 Johnson County

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

Soil pH

Your soil pH (5.3–7.0) overlaps with Microgreens's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Microgreens.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Microgreens.

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

38
successive plantings in your 195-day season

Sow every 0.7 weeks. Last sowing by Oct 05 to harvest before frost.

For a dedicated fall crop, sow by Aug 17.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/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 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 3.4" 0" ❄️ Dormant
Feb 4.2" 0" ❄️ Dormant
Mar 5.1" 0" ❄️ Dormant
Apr 4.3" 4.1" 0.2" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 4.6" 0" ✅ Rainfall sufficient
Jul 4.3" 4.6" 0" ✅ Rainfall sufficient
Aug 4.3" 4.4" 0" ✅ Rainfall sufficient
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 3.6" 0" ❄️ Dormant
Dec 3.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Johnson 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 ~203 GDD — county provides 2,827 GDD Excellent fit

Microgreens Planting Timeline — Johnson County, KY

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 – Mar 24
Transplant Outdoors April 14 Apr 14 – Apr 28
Direct Sow March 31 Mar 31 – Apr 21
Harvest April 21 Apr 21 – May 19
Fall Sowing August 17 Aug 17 – Aug 31

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

7–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

195 days in Johnson County

Growing Tips for Microgreens in Johnson County

Direct sow Microgreens outdoors after April 14 in Johnson County when soil has warmed and frost danger has passed.

Your generous 195.0-day season in Johnson 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 Johnson County, KY?

Johnson County is in Zone 7a with an average last frost of April 14. Plan your Microgreens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, KY?

Johnson County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 14 and first fall frost is October 26.

🌱

Your Johnson County Garden Planner — Free

A 24-page printable planner built for Johnson 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Johnson County, KY. 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.