Blog

When to Plant Horehound in Clark County, KY

Horehound is a woolly, drought-tolerant perennial herb traditionally used for cough remedies and candy. It has a distinctive bitter, menthol-like flavor.

Clark County, Kentucky is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 24, giving you a growing season of approximately 191 days.

At an elevation of 3,545 feet, Clark County receives approximately 50.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Horehound during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Horehound root diseases.

Clark County, KY (Zone 6b) Moderate season
191 days
Last Spring Frost April 16
191 growing days
First Fall Frost October 24

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (52 days to spare)
Transplant: Apr 16 🍅 Harvest: Jul 2 – Aug 27
Recommended (50%) ✓ Fits season (51 days to spare)
Transplant: Apr 23 🍅 Harvest: Jul 9 – Sep 3
Safe Start (90%) ✓ Fits season (42 days to spare)
Transplant: May 11 🍅 Harvest: Jul 27 – Sep 21

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 Clark County

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

Soil pH

Your soil pH (5.7โ€“6.8) overlaps with Horehound's range (6.0โ€“8.0), though not a perfect match.

Soil Texture

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

Drainage

Horehound prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Horehound.

How to Plant Horehound

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Horehound

2
successive plantings in your 191-day season

Sow every 8.6 weeks. Last sowing by Jul 26 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Horehound

Horehound needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Horehound Needs Rainfall You Supplement Action
Jan โ€” 4.6" 0" โ„๏ธ Dormant
Feb โ€” 3.8" 0" โ„๏ธ Dormant
Mar โ€” 4.7" 0" โ„๏ธ Dormant
Apr 2.2" 4.2" 0" โœ… Rainfall sufficient
May 2.2" 4.5" 0" โœ… Rainfall sufficient
Jun 2.2" 4.5" 0" โœ… Rainfall sufficient
Jul 2.2" 4.8" 0" โœ… Rainfall sufficient
Aug 2.2" 4.4" 0" โœ… Rainfall sufficient
Sep 2.2" 3.6" 0" โœ… Rainfall sufficient
Oct 2.2" 3.2" 0" โœ… Rainfall sufficient
Nov โ€” 4.1" 0" โ„๏ธ Dormant
Dec โ€” 4.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Clark County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Horehound 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" โ€” every day above 50ยฐF 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.

Horehound needs ~1,506 GDD — county provides 3,485 GDD Excellent fit

Horehound Planting Timeline โ€” Clark County, KY

Horehound Planting Calendar

Activity When Date Range
Transplant Outdoors April 23 Apr 23 โ€“ May 7
Harvest July 9 Jul 9 โ€“ Sep 3

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
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

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

75โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“8 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

191 days in Clark County

Growing Tips for Horehound in Clark County

Direct sow Horehound outdoors after April 16 in Clark County when soil has warmed and frost danger has passed.

General growing tips

Direct sow or start from divisions. Thrives in poor, dry soil. Harvest stems just before flowering. Deadhead to prevent aggressive self-seeding. Very drought-tolerant once established.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Horehound in Clark County, KY?

Clark County is in Zone 6b with an average last frost of April 16. Plan your Horehound planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clark County, KY?

Clark County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clark 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 Clark County, KY. Local conditions may vary. Last updated: April 2026.