''Tetragonia tetragonioides'', commonly called New Zealand spinach, Warrigal greens and other local names, is a flowering plant in the fig-marigold family (

Aizoaceae The Aizoaceae, or fig-marigold family, is a large family of dicotyledonous flowering plants containing 135 genera and about 1800 species. They are commonly known as ice plants or carpet weeds. They are often called vygies in South Africa and Ne ...

). It is often cultivated as a leafy vegetable. It is a widespread species, native to eastern Asia, Australia, and New Zealand. It has been introduced and is an invasive species in many parts of Africa, Europe, North America, and South America. Its natural habitat is sandy shorelines and bluffs, often in disturbed areas. It is a

halophyte A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity, coming into contact with saline water through its roots or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs and seashores. Th ...

and grows well in saline ground.

Description

The plant has a trailing habit, and will form a thick carpet on the ground or climb through other vegetation and hang downwards. It can have erect growth when young. 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

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s of the plant are yellow, and the

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a small, hard capsule covered with small horns.

Taxonomy

Prussian naturalist

Peter Pallas Peter Simon Pallas Fellow of the Royal Society, FRS FRSE (22 September 1741 – 8 September 1811) was a Prussian zoologist and botanist who worked in Russia between 1767 and 1810. Life and work Peter Simon Pallas was born in Berlin, the son ...

described the species as ''Demidovia tetragonoides'' in 1781. German botanist Otto Kuntze placed the species in the genus ''Tetragonia'' in his 1891 work ''

Revisio Generum Plantarum ''Revisio Generum Plantarum'', also known by its standard botanical abbreviation ''Revis. Gen. Pl.'', is a botanic treatise by Otto Kuntze. It was published in three volumes; the first two of these appeared in 1891, and the third was published in ...

'', resulting in its current binomial name. This widely distributed plant has many common names, depending on its location. In addition to the name New Zealand spinach, it is also known as

Botany Bay Botany Bay (Dharawal: ''Kamay''), an open oceanic embayment, is located in Sydney, New South Wales, Australia, south of the Sydney central business district. Its source is the confluence of the Georges River at Taren Point and the Cook ...

spinach, Cook's cabbage, ''kōkihi'' (in

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the C ...

), sea spinach, and tetragon. Its Australian names of Warrigal Greens and Warrigal Cabbage come from the local use of ''

warrigal The dingo (''Canis familiaris'', ''Canis familiaris dingo'', ''Canis dingo'', or ''Canis lupus dingo'') is an ancient (Basal (phylogenetics), basal) lineage of dog found in Australia (continent), Australia. Its taxonomic classification is de ...

'' to describe plants that are wild (not farmed originally).

Cultivation

It is grown for the edible leaves, and can be used as food or an

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

for ground cover. It can be an annual or perennial. As some of its names signify, it has similar flavour and texture properties to spinach, and is cooked like spinach. Like spinach, it contains

oxalate Oxalate (IUPAC: ethanedioate) is an anion with the formula C2O42−. This dianion is colorless. It occurs naturally, including in some foods. It forms a variety of salts, for example sodium oxalate (Na2C2O4), and several esters such as dimethyl ...

s; its medium to low levels of oxalates need to be removed by

blanching Blanch or blanching may refer to: People * Andrea Blanch (born 1935), portrait, commercial, and fine art photographer * Arnold Blanch (1896–1968), born and raised in Mantorville, Minnesota * Stuart Blanch, Baron Blanch (1918–1994), Anglican bi ...

the leaves in hot water for one minute, then rinsing in cold water before cooking. It thrives in hot weather, and is considered an

heirloom vegetable An heirloom plant, heirloom variety, heritage fruit (Australia and New Zealand), or heirloom vegetable (especially in Ireland and the UK) is an old cultivar of a plant used for food that is grown and maintained by gardeners and farmers, particular ...

. Few insects consume it, and even slugs and

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class G ...

s do not seem to feed on it. The thick, irregularly-shaped

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s 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 deep, and spaced apart. The seedlings will emerge in 10–20 days, and it will continue to produce greens through the summer. Mature plant will self-seed. Seeds will overwinter up to USDA zone 5.

As food

The species, rarely used by indigenous people as a

leaf vegetable Leaf vegetables, also called leafy greens, pot herbs, vegetable greens, or simply greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Leaf vegetables eaten raw in a salad can be called salad gre ...

, was first mentioned by

Captain Cook James Cook (7 November 1728 Old Style date: 27 October – 14 February 1779) was a British explorer, navigator, cartographer, and captain in the British Royal Navy, famous for his three voyages between 1768 and 1779 in the Pacific Ocean and ...

. It was immediately picked, cooked, and

pickled Pickling is the process of preserving or extending the shelf life of food by either anaerobic fermentation in brine or immersion in vinegar. The pickling procedure typically affects the food's texture and flavor. The resulting food is called ...

to help fight

scurvy Scurvy is a disease resulting from a lack of vitamin C (ascorbic acid). Early symptoms of deficiency include weakness, feeling tired and sore arms and legs. Without treatment, decreased red blood cells, gum disease, changes to hair, and bleeding ...

, and taken with the crew of the ''Endeavour''. It spread when the explorer and botanist Joseph Banks took seeds back to

Kew Gardens Kew Gardens is a botanic garden in southwest London that houses the "largest and most diverse botanical and mycological collections in the world". Founded in 1840, from the exotic garden at Kew Park, its living collections include some of the ...

during the latter half of the 18th century. For two centuries, ''T. tetragonioides'' was the only cultivated vegetable to have originated from Australia and New Zealand. There are some indications that Māori did eat ''kōkihi'' perhaps more regularly. According to Murdoch Riley, "to counteract the bitterness of the older leaves of this herb, the Māori boiled it with the roots of the convolvulus (''pōhue'')", in reference to species of

Convolvulaceae Convolvulaceae (), commonly called the bindweeds or morning glories, is a family of about 60 genera and more than 1,650 species. These species are primarily herbaceous vines, but also include trees, shrubs and herbs. The tubers of several spe ...

now classified as ''

Calystegia ''Calystegia'' (bindweed, false bindweed, or morning glory) is a genus of about 25 species of flowering plants in the bindweed family Convolvulaceae. The genus has a cosmopolitan distribution in temperate and subtropical regions, but with half o ...

''. The tips of the spinach can be pinched off and eaten raw or cooked.

Nutrition

When consumed after boiling, New Zealand spinach is 95% water, 2%

carbohydrate In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or m ...

s, 1%

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

, and contains negligible

fat In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (triple est ...

, while supplying only 12 calories (table). In a 100 gram reference amount, the spinach is particularly rich in

vitamin K Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-synthesis modification of certain proteins that are required for blood coagulation ...

, providing 278% of the

Daily Value The Reference Daily Intake (RDI) used in nutrition labeling on food and dietary supplement products in the U.S. and Canada is the daily intake level of a nutrient that is considered to be sufficient to meet the requirements of 97–98% of healthy ...

(DV). It also contains appreciable amounts of

vitamin B6 Vitamin B6 is one of the B vitamins, and thus an essential nutrient. The term refers to a group of six chemically similar compounds, i.e., " vitamers", which can be interconverted in biological systems. Its active form, pyridoxal 5′-phosp ...

vitamin C Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) ...

, and

manganese Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy use ...

(18-25% DV).

Gallery

File:Tetragonia flower MRD Otari.jpg, Flower File:Tetragonia tetragonioides (Flower).jpg, ''T. tetragonioides'' showing erect growth

References

External links

* {{Authority control tetragonioides Bushfood Caryophyllales of Australia Crops originating from Argentina Crops originating from Asia Crops originating from Australia Crops originating from Chile Crops originating from New Zealand Eudicots of Western Australia Flora of Japan Flora of New South Wales Flora of Norfolk Island Flora of Lord Howe Island Flora of South Australia Flora of Queensland Flora of Tasmania Flora of Victoria (Australia) Leaf vegetables