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When to Plant Catnip in Hamilton County, TN

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.

Hamilton County, Tennessee is in USDA Zone 7a. The average last spring frost is March 28 and the first fall frost is November 1, giving you a growing season of approximately 218 days.

At an elevation of 3,918 feet, Hamilton County receives approximately 51.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93ยฐF, providing good warmth for Catnip during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Catnip root diseases.

Hamilton County, TN (Zone 7a) Long season
218 days
Last Spring Frost March 28
218 growing days
First Fall Frost November 1

Hamilton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (88 days to spare)
Transplant: Mar 28 🍅 Harvest: May 30 – Aug 1
Recommended (50%) ✓ Fits season (85 days to spare)
Transplant: Apr 4 🍅 Harvest: Jun 6 – Aug 8
Safe Start (90%) ✓ Fits season (85 days to spare)
Transplant: Apr 24 🍅 Harvest: Jun 26 – Aug 28

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
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Catnip needs ~1,382 GDD — county provides 4,305 GDD Excellent fit

Catnip Planting Timeline โ€” Hamilton County, TN

Catnip Planting Calendar

Activity When Date Range
Transplant Outdoors April 4 Apr 4 โ€“ Apr 18
Harvest June 6 Jun 6 โ€“ Aug 8

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 โ€”
June Harvest
July Harvest
August Harvest
September โ€”
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 7a

Growing Season

218 days

Growing Tips for Hamilton 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 Hamilton County, TN?

Hamilton County is in Zone 7a with an average last frost of March 28. Plan your Catnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hamilton County, TN?

Hamilton County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is March 28 and first fall frost is November 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Hamilton County gardeners in Zone 7a 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 Hamilton County, TN. Local conditions may vary. Last updated: April 2026.