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When to Plant Catnip in Coos County, NH

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.

Coos County, New Hampshire is in USDA Zone 4a. The average last spring frost is May 18 and the first fall frost is September 30, giving you a growing season of approximately 135 days.

At an elevation of 604 feet, Coos County receives approximately 40.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Catnip to ensure they mature before fall.

Coos County, NH (Zone 4a) Short season
135 days
Last Spring Frost May 18
135 growing days
First Fall Frost September 30

Coos County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 18 🍅 Harvest: Jul 20 – Sep 21
Recommended (50%) ✓ Fits season (2 days to spare)
Transplant: May 25 🍅 Harvest: Jul 27 – Sep 28
Safe Start (90%) ✓ Fits season (4 days to spare)
Transplant: Jun 9 🍅 Harvest: Aug 11 – Oct 13

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.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.3″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Catnip needs ~910 GDD — county provides 1,755 GDD Excellent fit

Catnip Planting Timeline โ€” Coos County, NH

Catnip Planting Calendar

Activity When Date Range
Transplant Outdoors May 25 May 25 โ€“ Jun 8
Harvest July 27 Jul 27 โ€“ Sep 28

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

60โ€“80 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 4a

Growing Season

135 days

Growing Tips for Coos County

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

Frequently Asked Questions

When should I plant Catnip in Coos County, NH?

Coos County is in Zone 4a with an average last frost of May 18. Plan your Catnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Coos County, NH?

Coos County, New Hampshire is in USDA Hardiness Zone 4a. The average last spring frost is May 18 and first fall frost is September 30.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Coos County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.

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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 Coos County, NH. Local conditions may vary. Last updated: April 2026.