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When to Plant Amaranth in Durham County, NC

Amaranth is an ancient grain crop with edible leaves and seeds, rich in protein and micronutrients. It thrives in warm conditions and is drought-tolerant once established.

Durham County, North Carolina is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is November 3, giving you a growing season of approximately 215 days.

At an elevation of 727 feet, Durham County receives approximately 40.1 inches of rainfall annually with predominantly clay loam soil. Summer highs average 90ยฐF, providing good warmth for Amaranth during the growing season. Clay soil retains moisture well for Amaranth, but amend with compost to improve drainage and prevent root rot.

Durham County, NC (Zone 7b) Long season
215 days
Last Spring Frost April 2
215 growing days
First Fall Frost November 3

Durham County Soil Profile

Soil Type

Clay Loam

Soil pH

5.6-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (64 days to spare)
Start indoors: Feb 3 Transplant: Apr 7 🍅 Harvest: Jul 7 – Aug 25
Recommended (50%) ✓ Fits season (61 days to spare)
Start indoors: Feb 12 Transplant: Apr 16 🍅 Harvest: Jul 16 – Sep 3
Safe Start (90%) ✓ Fits season (56 days to spare)
Start indoors: Mar 3 Transplant: May 5 🍅 Harvest: Aug 4 – Sep 22

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 Durham County

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

Soil pH

Your soil pH (5.6โ€“6.7) overlaps with Amaranth's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The clay loam soil in Durham County is excellent for Amaranth โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Amaranth.

How to Plant Amaranth

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 415 gal / 100 sq ft

Monthly Watering Guide for Amaranth

Amaranth needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Amaranth Needs Rainfall You Supplement Action
Jan โ€” 3.6" 0" โ„๏ธ Dormant
Feb โ€” 3.3" 0" โ„๏ธ Dormant
Mar โ€” 3.8" 0" โ„๏ธ Dormant
Apr 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
May 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Jun 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Jul 4.3" 4.4" 0" โœ… Rainfall sufficient
Aug 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Sep 4.3" 3" 1.3" ๐Ÿ’ง Light watering
Oct 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Nov 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Dec โ€” 3.4" 0" โ„๏ธ Dormant

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

Amaranth 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.

Amaranth needs ~1,838 GDD — county provides 3,762 GDD Excellent fit

Amaranth Planting Timeline โ€” Durham County, NC

Amaranth Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 โ€“ Feb 26
Transplant Outdoors April 16 Apr 16 โ€“ Apr 30
Direct Sow April 9 Apr 9 โ€“ Apr 30
Harvest July 16 Jul 16 โ€“ Sep 3

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

215 days in Durham County

Growing Tips for Amaranth in Durham County

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

With Durham County's clay soil (31% clay), work in 3-4 inches of compost before planting Amaranth. Avoid tilling when soil is wet to prevent compaction.

General growing tips

Direct sow after last frost when soil is warm. Thin seedlings to 18 inches apart. Harvest leaves when young and tender; harvest seeds when flower heads begin to dry.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Amaranth in Durham County, NC?

Durham County is in Zone 7b with an average last frost of April 2. Plan your Amaranth planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Durham County, NC?

Durham County, North Carolina is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is November 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Durham 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 Durham County, NC. Local conditions may vary. Last updated: April 2026.