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When to Plant Cumin in Obion County, TN

Obion County, Tennessee Zone 7b May

What to do in May

Welcome to May in Zone 7b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 2
Avg. first frost October 28
Soil temp (4") 68°F
Watering Moderate
Pest pressure Moderate
Daylight 13.9 hrs
  1. Start cumin indoors

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

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Cumin is a warm-season annual herb whose seeds are one of the most widely used spices globally. It requires a long, hot growing season of 3-4 months.

Obion County, Tennessee is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is October 28, giving you a growing season of approximately 209 days.

At an elevation of 1,431 feet, Obion County receives approximately 44.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Cumin during the growing season.

Obion County, TN (Zone 7b) Long season
209 days
Last Spring Frost April 2
209 growing days
First Fall Frost October 28

Obion County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (47 days to spare)
Start indoors: Feb 20 Transplant: Mar 20 🍅 Harvest: Jul 3 – Sep 4
Recommended (50%) ✓ Fits season (48 days to spare)
Start indoors: Feb 26 Transplant: Mar 26 🍅 Harvest: Jul 9 – Sep 10
Safe Start (90%) ✓ Fits season (56 days to spare)
Start indoors: Mar 15 Transplant: Apr 12 🍅 Harvest: Jul 26 – Sep 27

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 Obion County

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

Soil pH

Your soil pH (5.2–7.0) overlaps with Cumin's range (6.0–8.0), though not a perfect match.

Soil Texture

The silt loam soil in Obion County is excellent for Cumin — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Cumin.

How to Plant Cumin

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

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

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Cumin

Cumin 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 Cumin Needs Rainfall You Supplement Action
Jan 3.1" 0" ❄️ Dormant
Feb 3.7" 0" ❄️ Dormant
Mar 4" 0" ❄️ Dormant
Apr 2.2" 2.9" 0" ✅ Rainfall sufficient
May 2.2" 3.7" 0" ✅ Rainfall sufficient
Jun 2.2" 3.9" 0" ✅ Rainfall sufficient
Jul 2.2" 4.4" 0" ✅ Rainfall sufficient
Aug 2.2" 4.6" 0" ✅ Rainfall sufficient
Sep 2.2" 3.7" 0" ✅ Rainfall sufficient
Oct 2.2" 2.8" 0" ✅ Rainfall sufficient
Nov 3.1" 0" ❄️ Dormant
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Obion County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Cumin 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" — every day above 50°F 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.

Cumin needs ~1,842 GDD — county provides 3,500 GDD Excellent fit

Cumin Planting Timeline — Obion County, TN

Cumin Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors March 26 Mar 26 – Apr 9
Direct Sow March 19 Mar 19 – Apr 9
Harvest July 9 Jul 9 – Sep 10
Fall Sowing August 19 Aug 19 – Sep 2

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

100–120 days

🧪 Soil pH

Needs 6–8 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

209 days in Obion County

Growing Tips for Cumin in Obion County

Direct sow Cumin outdoors after April 02 in Obion County when soil has warmed and frost danger has passed.

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

General growing tips

Start seeds indoors 4 weeks before last frost. Transplant after all danger of frost. Harvest when seed heads turn brown. Requires consistent warmth for proper seed development.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cumin in Obion County, TN?

Obion County is in Zone 7b with an average last frost of April 2. Plan your Cumin planting based on this frost date — see the calendar above for exact timing.

What planting zone is Obion County, TN?

Obion County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is October 28.

🌱

Your Obion County Garden Planner — Free

A 24-page printable planner built for Obion County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Obion County, TN. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.