Amaranthus tricolor aka Chinese Amaranth

Amaranthus tricolor is an annual in the amaranth family. Gardeners know it as Joseph's coat or Chinese spinach. It comes from tropical Asia, though its wild origins remain unclear. People grow it across tropical and warm temperate regions. In Asia, it serves as a major leaf crop. Growers also raise it for its edible seeds and bright foliage.

Plants grow upright, with stout stems and many branches. Some develop a bushy shape or spread out loosely. Garden heights range from about 1–5 feet [0.3–1.5 metres]. Plants spread about 1–2 feet [0.3–0.6 metres]. Sources differ, with Florida guidance giving 4 feet [1.2 metres] as the upper height. The stems may show red, green, yellow, or purple tones. Plants often need stakes to keep them standing upright.

The leaves grow in an alternate pattern along the stems. Each simple leaf may be oval or lance-shaped. Its edge may be smooth or wavy. Leaves lack hairs and can show several colors together. These include green, yellow, red, pink, purple, gold, and copper. The foliage gives the plant most of its garden value. Small flower spikes form where leaves meet the stem. Flowers appear in summer and fall but draw little attention. Sources report red, green, or yellow flowers. Small, dry fruits also draw little notice.

Grow this plant in sun, with shelter from harsh conditions. Full sun helps bring out strong leaf colors. It also grows in part shade, including late afternoon shade. It accepts clay, loam, and sand, provided water drains well. Keep the soil moist without leaving it waterlogged. The plant withstands heat, poor soil, and some drought. Too much fertilizer can weaken its leaf color. Sow seeds to raise new plants. Set plants outdoors once the risk of frost has passed. Its UK hardiness rating is H2; it does not survive freezing.

Use it in beds, borders, pots, or groups for foliage color. It also suits an edible garden and needs no pruning. Aphids and viruses can affect plants. Wet soil can lead to root rot or Phytophthora blight. Florida guidance reports no major pest or disease concerns. Leaves and seeds are edible, but food safety needs care. Plants grown in nitrogen-rich soil can collect nitrates in their leaves. The available evidence therefore cautions against eating plants raised with chemical fertilizers.