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When to plant Thyme in Mercer County, KY

In Mercer County, Thyme is a spring-only crop. Plant April 20–May 4 once soil hits 50°F.

When to Plant Thyme in Mercer County, KY

Thyme

Thyme is a low-growing perennial herb with tiny, aromatic leaves and a warm, earthy flavor. It is one of the most versatile culinary and medicinal herbs.

Mercer County, Kentucky is in USDA Zone 7a. The average last spring frost is April 13 and the first fall frost is October 26, giving you a growing season of approximately 196 days.

At an elevation of 1,559 feet, Mercer County receives approximately 54.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Thyme during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Thyme root diseases.

Mercer County, KY (Zone 7a) Moderate season
196 days
Last Spring Frost April 13
196 growing days
First Fall Frost October 26

Mercer County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.6

Drainage

Well Drained

Monthly Watering Guide for Thyme

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

Month Thyme Needs Rainfall You Supplement Action
Jan 4.6" 0" ❄️ Dormant
Feb 4.9" 0" ❄️ Dormant
Mar 4.7" 0" ❄️ Dormant
Apr 4.3" 4.3" 0" ✅ Rainfall sufficient
May 4.3" 4.3" 0" ✅ Rainfall sufficient
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 5.7" 0" ✅ Rainfall sufficient
Aug 4.3" 5.5" 0" ✅ Rainfall sufficient
Sep 4.3" 4.6" 0" ✅ Rainfall sufficient
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 4.4" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

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

Thyme Planting Timeline — Mercer County, KY

Thyme Planting Calendar

Activity When Date Range
Transplant Outdoors April 20 Apr 20 – May 4
Harvest June 29 Jun 29 – Aug 31

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June Harvest
July Harvest
August Harvest
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

196 days in Mercer County

Growing Tips for Mercer County

Start from seed, cuttings, or divisions. Plant in well-drained, lean soil. Prune lightly after flowering. Replace plants every 3-4 years when they become woody.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Thyme in Mercer County, KY?

Mercer County is in Zone 7a with an average last frost of April 13. Plan your Thyme planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mercer County, KY?

Mercer County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 13 and first fall frost is October 26.

When should I plant Thyme in Mercer County, KY?

In Mercer County, KY, plant Thyme after the last frost (around April 13) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Mercer County, KY for Thyme?

Mercer County sits in USDA Zone 7a. Thyme grows reliably in zones 4a through 9b, so it's a good fit here.

Can Thyme grow in Mercer County's climate?

Yes — Thyme grows well in Mercer County's temperate climate. Mercer County averages a 196-day frost-free season, with last frost around April 13 and first frost around October 26.

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Your Mercer County Garden Planner — Free

A 22-page printable planner built for Mercer 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.

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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 Mercer County, KY. Local conditions may vary. Last updated: June 2026.

Sources & credits

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