Tetragonia | ||||||||||||
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Tetragonia tetragonioides | ||||||||||||
Plant Info | ||||||||||||
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Scientific classification | ||||||||||||
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Species | ||||||||||||
About 50-60 species, including: Tetragonia angustifolia |
Tetragonia is a genus of 50-60 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions of the Southern Hemisphere, in New Zealand, Australia, southern Africa and South America. Common names include New Zealand Spinach, Kokihi (Māori language), Warrigal Greens, Sea Spinach, Botany Bay Spinach, Duneweed (South Africa), and Cook's Cabbage.
The genus, widely used by Māori and other indigenous people as a leaf vegetable, was first mentioned by Captain Cook. It was immediately picked, cooked, and pickled to help fight scurvy, and taken with the crew. It spread when the explorer and botanist Joseph Banks took a viable plant back to London during the latter half of the 18th century.
The species prefer a moist environment for growth. The plant grows flat on the ground. The leaves of the plant are 3-15 cm long, triangular in shape and bright green. The leaves are thick, and covered with tiny papillae that look like waterdrops on the top and bottom of the leaves. The flowers of the plant are yellow, and the fruit is a small, hard pod covered with small horns. The plant is a halophyte and grows well in saline ground.
Cultivation
It is grown for the edible leaves, and can be used as food or an ornamental plant for ground cover. As some of its names signify, it has similar flavour and texture properties to spinach, and is cooked like spinach, although some, perhaps all species contain mild toxins which need to be removed by blanching the leaves in hot water for one minute, then rinsing in cold water before cooking. It can be found as an invasive plant in North and South America, and has been cultivated along the East Asian rim. It thrives in hot weather, and is considered an heirloom vegetable. Few insects will bother it, and even slugs and snails do not seem to bother it.
The thick, irregularly-shaped seeds should be planted just after the last spring frost. Before planting, the seeds should be soaked for 12 hours in cold water, or 3 hours in warm water. Seeds should be planted 5-10 mm deep, and spaced 15-30 cm apart. The seedlings will emerge in 10-20 days, and it will continue to produce greens through the summer.