Thunberg's amaranth (Amaranthus thunbergii)

Thunberg's amaranth

Amaranthus thunbergii

Feathery plumes of tiny blooms add soft texture to garden borders. Annual herbaceous flowering plant; common name: Thunberg's amaranth.

Full sun
1–2/week
Beginner
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Plant Needs

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Sunlight Full sun to partial sun; tolerates mild shade but produces the most abundant blooms in direct sunlight
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Watering Water when the top 2–3 cm of soil feels dry; avoid overwatering to prevent root rot
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Temperature Thrives in warm temperatures; sensitive to frost, avoid exposure below 10°C
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Characteristics

  • Leaf: Simple, ovate to lanceolate, bright green, smooth margin, 5–12 cm long
  • Flower: Dense, feathery terminal spikes of tiny greenish-white or pale pink blooms
  • Stem: Erect, branched, green to reddish-green, smooth texture
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Care Guide

Watering

Keep soil consistently moist but not waterlogged

Fertilization

Diluted balanced liquid feed every 2 weeks. Avoid over-fertilizing to prevent excessive foliage growth at the expense of blooms

Banana peel compost tea:Compost banana peels for 2 weeks, steep in water for 24 hours, dilute 1:20 for root drench; avoid raw peels to prevent pest infestations
Pruning
  • Deadhead spent blooms regularly to encourage prolonged flowering
  • Thin overcrowded stems to improve airflow and reduce disease risk
  • Cut back the entire plant after flowering to collect seeds or clear garden beds for winter
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Toxicity

Warning: this plant may be toxic.

Pets & Humans

Pets: ASPCA: Non-toxic to cats; no reported adverse effects

Humans: No known toxic effects on humans; young leaves are edible in some cuisines

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Garden Uses & Culture

Culture: N/A

Usage: Ornamental garden border plant; young leaves are edible in some traditional Asian cuisines