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When to Plant Arugula in Hardeman County, TN

Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.

Hardeman County, Tennessee is in USDA Zone 7b. The average last spring frost is March 30 and the first fall frost is October 30, giving you a growing season of approximately 214 days.

At an elevation of 3,185 feet, Hardeman County receives approximately 48.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92ยฐF, providing good warmth for Arugula during the growing season.

Hardeman County, TN (Zone 7b) Long season
214 days
Last Spring Frost March 30
214 growing days
First Fall Frost October 30

Hardeman County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (117 days to spare)
Start indoors: Feb 17 Transplant: Mar 24 🍅 Harvest: Apr 28 – Jun 30
Recommended (50%) ✓ Fits season (116 days to spare)
Start indoors: Feb 23 Transplant: Mar 30 🍅 Harvest: May 4 – Jul 6
Safe Start (90%) ✓ Fits season (113 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: May 21 – Jul 23

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 Hardeman County

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

Soil pH

Your soil pH (5.2โ€“6.5) is more acidic than Arugula prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

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

How to Plant Arugula

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Arugula

8
successive plantings in your 214-day season

Sow every 3.4 weeks. Last sowing by Sep 10 to harvest before frost.

For a dedicated fall crop, sow by Aug 21.

Plant Water Budget

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

Monthly Watering Guide for Arugula

Arugula needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Arugula Needs Rainfall You Supplement Action
Jan โ€” 3.5" 0" โ„๏ธ Dormant
Feb โ€” 4.1" 0" โ„๏ธ Dormant
Mar 2.6" 5.2" 0" โœ… Rainfall sufficient
Apr 2.6" 3.7" 0" โœ… Rainfall sufficient
May 2.6" 3.7" 0" โœ… Rainfall sufficient
Jun 2.6" 3.7" 0" โœ… Rainfall sufficient
Jul 2.6" 5" 0" โœ… Rainfall sufficient
Aug 2.6" 4.6" 0" โœ… Rainfall sufficient
Sep 2.6" 4.1" 0" โœ… Rainfall sufficient
Oct 2.6" 3" 0" โœ… Rainfall sufficient
Nov โ€” 3.7" 0" โ„๏ธ Dormant
Dec โ€” 4.4" 0" โ„๏ธ Dormant

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

Arugula 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.

Arugula needs ~760 GDD — county provides 4,066 GDD Excellent fit

Arugula Planting Timeline โ€” Hardeman County, TN

Arugula Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 โ€“ Mar 9
Transplant Outdoors March 30 Mar 30 โ€“ Apr 13
Direct Sow March 16 Mar 16 โ€“ Apr 6
Harvest May 4 May 4 โ€“ Jul 6
Fall Sowing August 21 Aug 21 โ€“ Sep 4

Plant 0.5" deep ยท 6" 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

0.6"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

30โ€“50 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

214 days in Hardeman County

Growing Tips for Arugula in Hardeman County

Direct sow Arugula outdoors after March 30 in Hardeman County when soil has warmed and frost danger has passed.

Summer highs in Hardeman County reach 92ยฐF โ€” grow Arugula as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 214.0-day season in Hardeman County allows multiple plantings of Arugula. Sow every 15.0 days for continuous harvest.

Common pests for Arugula in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Arugula in Hardeman County, TN?

Hardeman County is in Zone 7b with an average last frost of March 30. Plan your Arugula planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hardeman County, TN?

Hardeman County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is March 30 and first fall frost is October 30.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Hardeman County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Hardeman County, TN. Local conditions may vary. Last updated: April 2026.