Tetragonia tetragonoides aka New Zealand Spinach

Tetragonia tetragonoides is part of the Aizoaceae plant family. Its names include New Zealand spinach and warrigal cabbage. It grows wild in southern China, Vietnam, and temperate East Asia. Its native range runs through Australasia to New Caledonia. Wild plants grow on dunes and stony beaches by the sea. In Australia, they also grow in salt marshes and dry plains.

This plant grows fast. It can live for one year or a few years. Gardeners often grow it as a yearly leaf crop. RHS gives its garden size as up to 1.6 feet [0.5 metres] tall and wide. Its text puts the height nearer 1 foot [0.3 metres]. Useful Tropical Plants reports creeping clumps over 3.3 feet [1 metre] wide. The leaves are somewhat fleshy and grow on upright stems. RHS says it sheds its leaves. Useful Tropical Plants says it stays green all year.

Grow it in full sun, with shelter from harsh conditions. Use soil that drains well and has a fair nutrient level. Keep the soil moist, not wet. Chalk, clay, loam, and sand all suit it. It accepts acid, neutral, and alkaline soil. RHS rates it H3, for mild and coastal UK sites. Keep plants safe from frost. Useful Tropical Plants lists warm temperate and tropical climates. It does not grow well in tropical lowlands. Cooler upland sites suit it.

Its main garden use is as a leafy food crop. It suits gardens by the coast and pots on patios. It also suits greenhouses and conservatories. Grow new plants from seed. RHS says plants reach full size in one to two years. They need no routine pruning. Reports list few pest or disease problems. Pick young shoot tips to spur more side shoots. Choose young leaves, as older ones can taste sharp. The leaves supply calcium and phosphorus.

Use leaves and young shoot tips in place of spinach. Sources say people eat them raw or cooked. The amount matters: avoid large raw servings. The plant has oxalates and saponins. Cooking cuts the amount of oxalic acid. Oxalates can reduce the calcium and other nutrients the body can use. Take extra care if prone to kidney stones, gout, or arthritis. Useful Tropical Plants also notes past use of leaves as medicine. It reports anti-ulcer effects in tests. These do not show proven treatment benefits.