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When to Plant Cilantro in Hamilton County, TN

Cilantro is a dual-purpose herb providing fresh leaves (cilantro) and dried seeds (coriander). It bolts quickly in heat, producing flowers beloved by beneficial insects.

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 Cilantro during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cilantro 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 (123 days to spare)
Start indoors: Feb 14 Transplant: Mar 14 🍅 Harvest: Apr 25 – Jun 27
Recommended (50%) ✓ Fits season (120 days to spare)
Start indoors: Feb 21 Transplant: Mar 21 🍅 Harvest: May 2 – Jul 4
Safe Start (90%) ✓ Fits season (120 days to spare)
Start indoors: Mar 13 Transplant: Apr 10 🍅 Harvest: May 22 – Jul 24

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 Hamilton County

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

Soil pH

Your soil pH (5.6โ€“6.9) overlaps with Cilantro's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Hamilton County is excellent for Cilantro โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.9%). Annual compost additions will help Cilantro.

How to Plant Cilantro

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Cilantro

6
successive plantings in your 218-day season

Sow every 4.6 weeks. Last sowing by Sep 02 to harvest before frost.

For a dedicated fall crop, sow by Aug 23.

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

Monthly Watering Guide for Cilantro

Cilantro 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 Cilantro Needs Rainfall You Supplement Action
Jan โ€” 4.3" 0" โ„๏ธ Dormant
Feb โ€” 4.5" 0" โ„๏ธ Dormant
Mar 2.2" 4.8" 0" โœ… Rainfall sufficient
Apr 2.2" 4" 0" โœ… Rainfall sufficient
May 2.2" 4.3" 0" โœ… Rainfall sufficient
Jun 2.2" 4.6" 0" โœ… Rainfall sufficient
Jul 2.2" 5.4" 0" โœ… Rainfall sufficient
Aug 2.2" 5.2" 0" โœ… Rainfall sufficient
Sep 2.2" 3.8" 0" โœ… Rainfall sufficient
Oct 2.2" 2.7" 0" โœ… Rainfall sufficient
Nov 2.2" 4.2" 0" โœ… Rainfall sufficient
Dec โ€” 3.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Hamilton County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Cilantro 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" โ€” every day above 50ยฐF 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.

Cilantro needs ~988 GDD — county provides 4,305 GDD Excellent fit

Cilantro Planting Timeline โ€” Hamilton County, TN

Cilantro Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 โ€“ Mar 7
Transplant Outdoors March 21 Mar 21 โ€“ Apr 4
Direct Sow March 14 Mar 14 โ€“ Apr 4
Harvest May 2 May 2 โ€“ Jul 4
Fall Sowing August 23 Aug 23 โ€“ Sep 6

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

218 days in Hamilton County

Growing Tips for Cilantro in Hamilton County

Direct sow Cilantro outdoors after March 28 in Hamilton County when soil has warmed and frost danger has passed.

Summer highs in Hamilton County reach 93ยฐF โ€” grow Cilantro as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 218.0-day season in Hamilton County allows multiple plantings of Cilantro. Sow every 20.0 days for continuous harvest.

Common pests for Cilantro in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Succession sow every 2-3 weeks. Provide afternoon shade in warm weather. Harvest leaves before flowering or allow some plants to go to seed for coriander and self-sowing.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cilantro in Hamilton County, TN?

Hamilton County is in Zone 7a with an average last frost of March 28. Plan your Cilantro 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.