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When to Plant Horehound in USDA Zone 3b

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

In Zone 3b, the average last spring frost is around May 10 and the first fall frost is around September 22, giving you a growing season of approximately 135 days.

Zone 3b Short season
135 days
Last Spring Frost May 10
135 growing days
First Fall Frost September 22

Horehound Planting Timeline — Zone 3b

Where Is USDA Zone 3b?

The map below highlights the states that contain Zone 3b. Click any state to see the Horehound planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Horehound Planting Calendar — Zone 3b

Activity When Date Range
Transplant Outdoors May 17 May 17 – May 31
Harvest August 2 Aug 2 – Sep 20

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

Month-by-Month Timeline

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

Free Zone 3b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 3b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

Days to Maturity

75–90 days

Soil pH

6 – 8

Zone Temperature Range

-35°F to -30°F average annual minimum

Growing Season

135 days (Zone 3b average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing8 inches apart
Row Spacing12 inches between rows

Succession Planting Horehound in Zone 3b

2
successive plantings in Zone 3b's ~135-day season

Sow every 8.6 weeks for continuous harvest throughout the season.

Growing Tips for Horehound in Zone 3b

Zone 3b has a short growing season (~135 days). Start Horehound indoors early and use season-extension techniques like row covers and cold frames.

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

Level Up Your Garden

Saving Horehound Seeds

Recommended for Your Garden

💡
LED Grow Lights $25-60

Full-spectrum LED lights for starting seeds indoors when daylight is limited.

🔥
Seedling Heat Mat $15-35

Warm soil for faster germination of heat-loving crops like tomatoes and peppers.

🪡
Floating Row Covers $12-30

Protect plants from frost, wind, and pests while letting light and water through.

Related Plants

Frequently Asked Questions

When should I plant Horehound in Zone 3b?

In Zone 3b, plan your Horehound planting around the average last frost date of May 10. Transplant seedlings around May 17.

Can Horehound grow in Zone 3b?

Yes, Horehound can grow well in Zone 3b, hardy in USDA zones 3a through 10b. Zone 3b has a growing season of approximately 135 days, which is sufficient for Horehound (75-90 days to maturity).

When can I harvest Horehound in Zone 3b?

In Zone 3b, expect to harvest Horehound from August 2 – September 20. Horehound takes 75-90 days from planting to harvest.

What is the last frost date for Zone 3b?

The average last spring frost in Zone 3b is around May 10, and the first fall frost is around September 22. This gives a growing season of approximately 135 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Horehound?

Good companion plants for Horehound include Tomatoes, Peppers. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 3b, track your crops, and plan your garden season from seed to harvest.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.