1 / 3

Amaranthus, Genus, spp., Multiple species,

Genus
Multiple species

amaranths

Amaranthaceae

Americas and Eurasia; warm regions of North and Central America

Attracts Pollinators Drought Tolerant Container Friendly

SunFull Sun

WaterLow · drought-tolerant

Overview

Amaranthus is a genus of about 75 species of fast-growing annual herbs in the family Amaranthaceae, known as amaranths and pigweeds. Plants range from 1 to 8 feet (0.3 to 2.4 m) tall on stout, often reddish stems, with alternate, oval to diamond-shaped leaves 2 to 8 inches (5 to 20 cm) long, sometimes flushed red, purple, or gold. The tiny flowers lack showy petals and are packed by the thousand into dense, branching or drooping spikes and tassels, green, red, crimson, or purple, with some kinds, such as love-lies-bleeding (A. caudatus), trailing long rope-like clusters. As C4 plants, amaranths grow rapidly in heat and full sun and set enormous quantities of small, shiny seed. The genus is now found worldwide and includes grain crops (A. cruentus and A. hypochondriacus), leafy vegetables grown across Asia and Africa, brightly colored ornamentals, and several aggressive farm weeds. Palmer amaranth (A. palmeri) and redroot pigweed (A. retroflexus) are difficult agricultural weeds, some with resistance to common herbicides. Amaranth foliage can accumulate nitrates and oxalates and may poison livestock if grazed heavily.

Native Range

The genus Amaranthus has species native to both the Americas and Eurasia, with the largest number originating in the warm regions of North and Central America. Through cultivation and as weeds, amaranths have spread to temperate and tropical regions worldwide. They grow in fields, gardens, floodplains, roadsides, and other open, disturbed, sunny ground.

Suggested Uses

Ornamental Amaranthus are planted for bold foliage and flower tassels in summer borders, cutting gardens, and large containers, spaced 10 to 18 inches (25 to 45 cm) apart, and the long tassels are used fresh or dried. Grain and leaf species are grown in vegetable plots and warm-season food gardens. The seed-laden spikes draw finches and other seed-eating birds in autumn.

How to Identify

Recognize Amaranthus by alternate, untoothed leaves on often red-tinged stems and very small petalless flowers crowded into dense bristly spikes, each flower backed by stiff dry bracts. Male and female flowers are separate, and ripe female flowers shed a single small shiny seed enclosed in a thin case that splits around the middle. Crushing reveals no scent, and seedlings of weedy species show a notch at the leaf tip and a reddish root. Ornamental and grain types differ mainly in stem color, leaf color, and the size and droop of the flower tassels.

Appearance

Size & Dimensions

Height1' - 8'

Width/Spread10" - 2'6"

Colors

Flower Colors

red

Foliage Colors

red

Fall Foliage Colors

Bloom Information

Bloom Period

~12 weeks

Flowers: July–October

Summer Fall

Amaranthus flowers from mid summer until the first frost, generally July through October, with the dense spikes coloring up over many weeks. The flowers themselves are minute, but the massed bracts and stems carry the green, red, crimson, gold, or purple color of the display. Wind moves the pollen, and seed begins ripening within the spikes while the upper flowers still open. A single large plant can produce hundreds of thousands of seeds.

Detailed Descriptions

Flower Description

green, red, crimson, gold, or purple

Foliage Description

green, often flushed red, purple, or gold

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-12 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 7.5 (Neutral to alkaline)

3579

Soil Types

loam sand clay

Drainagewell drained

Water & Climate

Water Needs

Low

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Amaranthus grows in full sun and average, well-drained soil across a pH of 6.0 to 7.5, tolerating heat, drought, and lean ground once established, though richer soil and steady moisture give larger plants. Seed is sown after the last frost when the soil has warmed, since the plants are killed by cold. Young plants need regular water, after which most kinds withstand dry spells. Tall ornamental and grain types may need staking on windy sites. Aphids, leaf miners, and root rot in wet soil are the main problems. Self-sown seedlings appear in quantity the following year and the weedy species spread quickly.

Pruning

Amaranthus needs little pruning as a fast annual. Pinching the growing tip of young plants produces a bushier habit and more, but shorter, flower tassels. Spent tassels are cut once they fade to limit heavy self-seeding, and whole plants are pulled and composted after frost. Grain types are cut at the stalk when the seed is ripe.

Pruning Schedule

Prune: June

summer