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Tri Color Amaranth (Joseph's Coat)

Ornamental Edible · Amaranthaceae

Striking tri-colored amaranth grown for colorful edible leaves and ornamental impact. Best grown in warm weather with steady moisture and harvested young for the mildest greens. Key facts: 30–45 days to maturity, 6+ hours of sun, 10–12 " spacing. Container-friendly (minimum 3-gallon pot).

Updated April 19, 2026 · Backed by 4 cited sources
Overview

At a Glance

The essentials first: timing, light, spacing, seed-starting, container fit, and overall size.

Days to maturity
30–45 days
Sun
6+ hours
Full Sun
Spacing
10–12 "
between plants
Seed start
3–4 weeks
before transplant
Container
Yes
3+ gallon pot
Height
2–4 ft
at maturity
Planting window

Zone Planting Guide

Switch zones to see whether this plant is a strong fit, what frost timing looks like, and any extra notes worth planning around.

This card updates instantly with viability, frost timing, and any planting notes for your selected zone.

Resilience

Plant Health

Stress tolerance, resistance notes, and the most common problems to watch for as plants mature.

Tolerance
Heat: High Cold: Low Drought: Moderate

Common Issues

Root Rot

Cause: Cold wet or poorly drained soils.

Prevention: Plant after soils warm and avoid overwatering.

Aphids

Cause: Tender new growth attracts sap-feeding insects.

Prevention: Use strong water sprays, encourage beneficials, and avoid excess nitrogen.

Leaf Toughness

Cause: Plants allowed to get too old before harvest.

Prevention: Cut young leaves regularly and keep water steady.

Feeding & picking

Nutrition & Harvest

How hungry the plant is, what ripe harvest looks like, and how long the crop keeps after picking.

Feeding
Nutrition
Feeding intensityModerate feeder
RecipesWorm Castings Topdress, Compost Tea
Timing
Harvest

Leaves are fully expanded, brightly colored, and still tender. Harvest before stems become fibrous.

Expected yield0.5–1.5 lbs/plant
Storage4 days — Refrigerate loosely wrapped and use while crisp.
Plant relationships

Companion Planting

Helpful neighbors can support growth or deter pests. Keep antagonistic plants separated to reduce stress and competition.

What you'll need

Growing Supplies

Based on Joseph's Coat Amaranth's growth profile -- recommendations matched to this variety's specific requirements.

Drip irrigation / soaker hose kit

Every gardener benefits from putting water at the root zone instead of on the leaves, because drip and soaker systems reduce foliar disease pressure by limiting leaf wetness and soil splash. A quality kit should include a backflow preventer, filter, pressure reducer, and UV-resistant tubing.

Source: Iowa State University Extension; Colorado State University Extension; UMass Extension

Soil test kit

A soil test gives a baseline for pH and nutrient status so gardeners can add only what the soil actually needs. Prioritize a mail-in or lab-affiliated kit whenever possible because extension guidance notes that laboratory testing is more accurate than instant readers.

Source: University of Maryland Extension; Purdue Extension; Montana State University Extension

Quality bypass pruners

Extension guidance favors bypass designs because they make cleaner, closer cuts on living tissue than anvil types. Look for hardened steel blades that can be sharpened, a comfortable grip, and a cutting capacity matched to real home-garden stems.

Source: University of New Hampshire Extension; Iowa State University Extension; Purdue University Extension

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Research

Sources

Reference material and extension guidance used to build this growing guide.

university North Carolina Extension Gardener Plant Toolboxuniversity Iowa State University Extension and Outreach Alternative Agriculturereference SeedsNow batch promptinference Estimated from edible amaranth leaf harvest windows and Amaranthus tricolor culture
Internal links

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