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When to Plant Catnip in USDA Zone 3b

Catnip is a hardy perennial herb in the mint family known for its effect on cats. It also makes a calming tea and is a useful companion plant that repels some pests.

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

Catnip 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 Catnip planting schedule for that location.

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

Catnip Planting Calendar — Zone 3b

Activity When Date Range
Transplant Outdoors May 17 May 17 – May 31
Harvest July 19 Jul 19 – 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 Harvest
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

60–80 days

Soil pH

6 – 7.5

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 Catnip in Zone 3b

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

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Catnip in Zone 3b

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

Direct sow or start indoors. Catnip is very easy to grow and can become invasive. Harvest leaves before flowering for tea. Protect young plants from cats.

Companion Planting

Good Companions

Level Up Your Garden

Saving Catnip 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 Catnip in Zone 3b?

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

Can Catnip grow in Zone 3b?

Yes, Catnip can grow well in Zone 3b, hardy in USDA zones 3a through 9b. Zone 3b has a growing season of approximately 135 days, which is sufficient for Catnip (60-80 days to maturity).

When can I harvest Catnip in Zone 3b?

In Zone 3b, expect to harvest Catnip from July 19 – September 20. Catnip takes 60-80 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 Catnip?

Good companion plants for Catnip include Squash Summer, Pumpkin, Beets. 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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Free download. Plan your entire garden season in minutes.

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.