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When to Plant Basil in Washington County, KY

Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.

Washington County, Kentucky is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 29, giving you a growing season of approximately 204 days.

At an elevation of 2,281 feet, Washington County receives approximately 43.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Basil during the growing season.

Washington County, KY (Zone 6b) Long season
204 days
Last Spring Frost April 8
204 growing days
First Fall Frost October 29

Washington 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 (72 days to spare)
Start indoors: Feb 12 Transplant: Apr 16 🍅 Harvest: Jun 11 – Aug 13
Recommended (50%) ✓ Fits season (71 days to spare)
Start indoors: Feb 18 Transplant: Apr 22 🍅 Harvest: Jun 17 – Aug 19
Safe Start (90%) ✓ Fits season (67 days to spare)
Start indoors: Mar 6 Transplant: May 8 🍅 Harvest: Jul 3 – Sep 4

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.

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 205 gal / 100 sq ft
Basil needs ~1,141 GDD — county provides 3,723 GDD Excellent fit

Basil Planting Timeline โ€” Washington County, KY

Basil Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 โ€“ Mar 4
Transplant Outdoors April 22 Apr 22 โ€“ May 6
Direct Sow April 15 Apr 15 โ€“ May 6
Harvest June 17 Jun 17 โ€“ Aug 19

Plant 0.5" deep ยท 8" apart ยท Rows 12" 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 Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“75 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

204 days

Growing Tips for Washington County

Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Level Up Your Garden

๐ŸŒพ Save Your Own Basil Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower spikes dry brown on the plant.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Isolate 150 ft between varieties. Different basil species can cross.

Frequently Asked Questions

When should I plant Basil in Washington County, KY?

Washington County is in Zone 6b with an average last frost of April 8. Plan your Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washington County, KY?

Washington County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 29.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

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 Washington County, KY. Local conditions may vary. Last updated: April 2026.