Amaranthus hybridus aka Hybrid Amaranth

Amaranthus hybridus is an annual in the amaranth family, Amaranthaceae. Common names include green amaranth, smooth pigweed, and callaloo. Its native range runs from southern Ontario to western South America. It now grows across the tropics and has naturalized in Europe. It grows wild in crop fields and on waste ground. People also grow it for its edible leaves and seeds.

The plant grows upright, with few or many side branches. Garden plants reach about 3.3–4.9 feet (1–1.5 metres) tall. They spread about 0.3–1.6 feet (0.1–0.5 metres). Broader accounts report heights up to 6.6 feet (2 metres). Some plants reach 8.2 feet (2.5 metres). The stems, leaves, and flowers are green, sometimes flushed red. Flower spikes appear in summer and autumn. Wind carries pollen, and the plant can also pollinate itself. It forms many small, shiny seeds, most often black. Some seeds are brown or reddish, and birds eat them.

Give this plant full sun and shelter from strong exposure. It prefers moist, fertile soil with plenty of humus. The soil should drain well, though the plant can withstand drought. It grows in clay, loam, sand, and chalk soils. It also accepts acid, neutral, and alkaline conditions. RHS rates its cold tolerance as H2; it cannot survive freezing. Sow seeds outdoors or start them indoors in spring. Pinch the main stem to help side shoots grow. Cut plants down once flowering ends.

This species suits flower beds, informal gardens, and wildlife plantings. Its flower stems can also serve as cut flowers. Fallen seeds can produce new plants without further sowing. Its ability to spread makes it a weed in many places. Watch for aphids, which may attack the plant. Viral disease may also occur. The whole plant can yield green and yellow dyes. Sources also record leaf tea as a traditional astringent remedy. This records a use, not proof that it works.

Young leaves can be eaten raw or cooked like spinach. Older leaves may become fibrous; brief boiling helps soften them. The seeds are edible raw, toasted, or boiled. They have a nutty taste when prepared. Food use needs care on soil rich in nitrogen. Leaves can build up nitrates, which pose a health risk. This concern matters where growers use heavy nitrogen fertilizer.