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When to Plant Marjoram in Decatur County, TN

Decatur County, Tennessee Zone 7b May

Your May gardening checklist

Your garden in Decatur County, Tennessee is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost April 5
Avg. first frost October 27
Soil temp (4") 68°F
Watering Low
Pest pressure Moderate
Daylight 13.9 hrs
Get ahead of June
  • First harvests: marjoram

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Sweet marjoram is a tender perennial herb with a delicate, sweet oregano-like flavor. It is a cornerstone of Mediterranean cooking and pairs well with meats and vegetables.

Decatur County, Tennessee is in USDA Zone 7b. The average last spring frost is April 5 and the first fall frost is October 27, giving you a growing season of approximately 205 days.

At an elevation of 1,168 feet, Decatur County receives approximately 55 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Marjoram during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Marjoram root diseases.

Decatur County, TN (Zone 7b) Long season
205 days
Last Spring Frost April 5
205 growing days
First Fall Frost October 27

Decatur County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (66 days to spare)
Transplant: Apr 4 🍅 Harvest: Jun 6 – Aug 15
Recommended (50%) ✓ Fits season (65 days to spare)
Transplant: Apr 12 🍅 Harvest: Jun 14 – Aug 23
Safe Start (90%) ✓ Fits season (66 days to spare)
Transplant: Apr 28 🍅 Harvest: Jun 30 – Sep 8

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 Decatur County

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

Soil pH

Your soil pH (5.3–6.5) is more acidic than Marjoram prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Marjoram.

How to Plant Marjoram

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

Succession Planting Marjoram

4
successive plantings in your 205-day season

Sow every 6.9 weeks. Last sowing by Jul 29 to harvest before frost.

Plant Water Budget

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

Monthly Watering Guide for Marjoram

Marjoram needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.

Month Marjoram Needs Rainfall You Supplement Action
Jan 4.2" 0" ❄️ Dormant
Feb 4" 0" ❄️ Dormant
Mar 4.6" 0" ❄️ Dormant
Apr 1.3" 4.5" 0" ✅ Rainfall sufficient
May 1.3" 4.5" 0" ✅ Rainfall sufficient
Jun 1.3" 5.4" 0" ✅ Rainfall sufficient
Jul 1.3" 6.5" 0" ✅ Rainfall sufficient
Aug 1.3" 5.6" 0" ✅ Rainfall sufficient
Sep 1.3" 3.6" 0" ✅ Rainfall sufficient
Oct 1.3" 3.1" 0" ✅ Rainfall sufficient
Nov 4" 0" ❄️ Dormant
Dec 4.9" 0" ❄️ Dormant

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

Marjoram 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.

Marjoram needs ~1,312 GDD — county provides 3,587 GDD Excellent fit

Marjoram Planting Timeline — Decatur County, TN

Marjoram Planting Calendar

Activity When Date Range
Transplant Outdoors April 12 Apr 12 – Apr 26
Harvest June 14 Jun 14 – Aug 23

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7b

📆 Growing Season

205 days in Decatur County

Growing Tips for Marjoram in Decatur County

Direct sow Marjoram outdoors after April 05 in Decatur County when soil has warmed and frost danger has passed.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Harvest stems just as flower buds appear for peak flavor. In cold climates, grow as an annual or bring containers indoors.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Marjoram in Decatur County, TN?

Decatur County is in Zone 7b with an average last frost of April 5. Plan your Marjoram planting based on this frost date — see the calendar above for exact timing.

What planting zone is Decatur County, TN?

Decatur County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 5 and first fall frost is October 27.

🌱

Your Decatur County Garden Planner — Free

A 24-page printable planner built for Decatur 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 Decatur 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.