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When to Plant Amaranth in Warren County, IN

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.

Warren County, Indiana is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 14, giving you a growing season of approximately 178 days.

At an elevation of 764 feet, Warren County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Amaranth during the growing season.

Warren County, IN (Zone 5b) Moderate season
178 days
Last Spring Frost April 19
178 growing days
First Fall Frost October 14

Warren County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (24 days to spare)
Start indoors: Feb 17 Transplant: Apr 28 🍅 Harvest: Jul 28 – Sep 15
Recommended (50%) ✓ Fits season (24 days to spare)
Start indoors: Feb 22 Transplant: May 3 🍅 Harvest: Aug 2 – Sep 20
Safe Start (90%) ✓ Fits season (23 days to spare)
Start indoors: Mar 10 Transplant: May 19 🍅 Harvest: Aug 18 – Oct 6

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 Warren County

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

Soil pH

Your soil pH (5.9โ€“7.1) overlaps with Amaranth's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.9%) โ€” Amaranth will thrive.

How to Plant Amaranth

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 55 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€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 1.6" 0" โ„๏ธ Dormant
Mar โ€” 2.8" 0" โ„๏ธ Dormant
Apr 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
May 4.3" 4.7" 0" โœ… Rainfall sufficient
Jun 4.3" 5.4" 0" โœ… Rainfall sufficient
Jul 4.3" 4.7" 0" โœ… Rainfall sufficient
Aug 4.3" 4.6" 0" โœ… Rainfall sufficient
Sep 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Oct 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Nov โ€” 2.7" 0" โ„๏ธ Dormant
Dec โ€” 2.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Warren 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 ~1,522 GDD — county provides 2,581 GDD Excellent fit

Amaranth Planting Timeline โ€” Warren County, IN

Amaranth Planting Calendar

Activity When Date Range
Start Indoors February 22 Feb 22 โ€“ Mar 8
Transplant Outdoors May 3 May 3 โ€“ May 17
Direct Sow April 26 Apr 26 โ€“ May 17
Harvest August 2 Aug 2 โ€“ Sep 20

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July โ€”
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 5b

๐Ÿ“† Growing Season

178 days in Warren County

Growing Tips for Amaranth in Warren County

Direct sow Amaranth outdoors after April 19 in Warren County when soil has warmed and frost danger has passed.

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 Warren County, IN?

Warren County is in Zone 5b with an average last frost of April 19. Plan your Amaranth planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Warren County, IN?

Warren County, Indiana is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 14.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Warren County gardeners in Zone 5b 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 Warren County, IN. Local conditions may vary. Last updated: April 2026.