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When to Plant Potatoes in Johnson County, KY

Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.

Johnson County, Kentucky is in USDA Zone 6b. 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 86ยฐF, providing good warmth for Potatoes during the growing season.

Johnson County, KY (Zone 6b) 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 (42 days to spare)
Start indoors: Feb 11 Transplant: Apr 22 🍅 Harvest: Jul 1 – Sep 9
Recommended (50%) ✓ Fits season (41 days to spare)
Start indoors: Feb 17 Transplant: Apr 28 🍅 Harvest: Jul 7 – Sep 15
Safe Start (90%) ✓ Fits season (38 days to spare)
Start indoors: Mar 7 Transplant: May 16 🍅 Harvest: Jul 25 – Oct 3

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 Potatoes's growing requirements.

Soil pH

Your soil pH (5.3โ€“7.0) overlaps with Potatoes's range (5.0โ€“6.5), though not a perfect match.

Soil Texture

The silt loam soil in Johnson County is excellent for Potatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Potatoes.

Organic Matter

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

How to Plant Potatoes

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Potatoes

3
successive plantings in your 195-day season

Sow every 8 weeks. Last sowing by Jun 28 to harvest before frost.

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 โ€” consider drought-tolerant varieties and mulching

Potatoes needs ~1,378 GDD — county provides 2,827 GDD Excellent fit

Potatoes Planting Timeline โ€” Johnson County, KY

Potatoes Planting Calendar

Activity When Date Range
Start Indoors February 17 Feb 17 โ€“ Mar 3
Transplant Outdoors April 28 Apr 28 โ€“ May 12
Direct Sow April 21 Apr 21 โ€“ May 12
Harvest July 7 Jul 7 โ€“ Sep 15

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

70โ€“120 days

๐Ÿงช Soil pH

Needs 5โ€“6.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

195 days in Johnson County

Growing Tips for Potatoes in Johnson County

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

Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Cucumber
  • Squash Summer

Level Up Your Garden

Frequently Asked Questions

When should I plant Potatoes in Johnson County, KY?

Johnson County is in Zone 6b with an average last frost of April 14. Plan your Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Johnson County, KY?

Johnson County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Johnson County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

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Free download. Plan your entire garden season in minutes.

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: April 2026.