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When to plant Horehound in Mapleton, IL

In Mapleton, Horehound is a spring-only crop. Plant April 30–May 14 once soil hits 50°F.

When to Plant Horehound in Mapleton, IL

Peoria County, Illinois Zone 6a August

August in Peoria County, Illinois — your action list

Welcome to August in Zone 6a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 23
Avg. first frost October 12
Soil temp (4") 78°F
Watering Moderate
Pest pressure High
Daylight 13.6 hrs
  1. It's harvest week for horehound

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

Coming up in September — start thinking about
  • First harvests: horehound

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

Mapleton, Illinois is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 12, giving you a growing season of approximately 172 days.

At an elevation of 884 feet, Peoria County receives approximately 33 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Horehound during the growing season.

Mapleton, IL (Zone 6a) Moderate season
172 days
Last Spring Frost April 23
172 growing days
First Fall Frost October 12

Mapleton Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7

Drainage

Well Drained

Horehound Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Transplant: Apr 24 🍅 Harvest: Jul 10 – Sep 4
Recommended (50%) ✓ Fits season (32 days to spare)
Transplant: Apr 30 🍅 Harvest: Jul 16 – Sep 10
Safe Start (90%) ✓ Fits season (33 days to spare)
Transplant: May 15 🍅 Harvest: Jul 31 – Sep 25

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 Mapleton

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

Soil pH

Your soil pH (6.1–7.0) is within Horehound's preferred range (6.0–8.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — Horehound will thrive.

How to Plant Horehound

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

Succession Planting Horehound

2
successive plantings in your 172-day season

Sow every 8.6 weeks. Last sowing by Jul 14 to harvest before frost.

Horehound Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/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 1.4" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 4.2" 0" ✅ Rainfall sufficient
Jun 2.2" 3.9" 0" ✅ Rainfall sufficient
Jul 2.2" 3.2" 0" ✅ Rainfall sufficient
Aug 2.2" 3.4" 0" ✅ Rainfall sufficient
Sep 2.2" 3.2" 0" ✅ Rainfall sufficient
Oct 2.2" 2.8" 0" ✅ Rainfall sufficient
Nov 1.9" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Peoria County). Supplement amounts are based on average rainfall — 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" — 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.

Horehound needs ~1,196 GDD — county provides 2,494 GDD Excellent fit

Horehound Planting Timeline — Mapleton, IL

Horehound Planting Calendar

Activity When Date Range
Transplant Outdoors April 30 Apr 30 – May 14
Harvest July 16 Jul 16 – Sep 10

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

75–90 days

🧪 Soil pH

Needs 6–8 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

172 days in Peoria County

Growing Tips for Horehound in Mapleton

Direct sow Horehound outdoors after April 23 in Peoria 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 →

When should I plant Horehound in Mapleton, IL?

In Mapleton, IL, plant Horehound after the last frost (around April 23) and before the first frost (around October 12). Best results when soil holds above 50°F.

What growing zone is Mapleton, IL for Horehound?

Mapleton sits in USDA Zone 6a. Horehound grows reliably in zones 3a through 10b, so it's a good fit here.

Can Horehound grow in Mapleton's climate?

Yes — Horehound grows well in Mapleton's temperate climate. Mapleton averages a 172-day frost-free season, with last frost around April 23 and first frost around October 12.

🌱

Your Peoria County Garden Planner — Free

A 22-page printable planner built for Peoria County (Zone 6a). 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 Peoria County, IL. Local conditions may vary. Last updated: August 2026.