Bower Spinach (Tetragonia implexicoma) and Sea Spinach (T. decumbens)
Common names: Bower Spinach, Sea Spinach
Taxonomic name: Tetragonia implexicoma, Tetragonia decumbens
Habitat: Tetragonia implexicoma prefers coastal woodland, T. decumbens can be found on dunes closer to the ocean.
Form: Scrambling plants that form patches of up to 5 m and may cover other plants and rocks
Flowering Time: All year
Kaurna name: Pirira
Bower Spinach (Tetragonia implexicoma) and Sea Spinach (Tetragonia decumbens) look pretty similar and are local relatives of the well known Warrigal Greens or New Zealand Spinach (Tetragonia tetragonioides) that restaurants love.
Sea Spinach is a plant that has naturalised in southern Australia and is originally from South Africa. Bower Spinach seems to like cooler, moist soils under trees near beaches and in the Mallee. Sea Spinach seems to prefers more open places such as on dunes.
Both species are easy to find, sprawling succulents (see below). They have leaves made shiny by the presence of many water storage cells. They are vigorous, sprawling, scrambling herbs, frequently with stems that are metres long that can cover rocks and shrubs. Both have reddish stems when young that get darker and browner with age.
Both have yellow flowers with usually 4 but sometimes 5 petals which incurve at the tips. Bower Spinach flowers become succulent pink/orange berries that change to black as they dry. Sea Spinach fruit is succulent and green and has 4 lobes.
Both usually establish themselves near or under trees and shrubs from which birds drop or poo out undigested seeds that are then provided with fertilizer and a little moisture by the poo itself.
Growing under trees and bushes, Bower Spinach forms the bowers from which it gets its common name, as well as its species name, ‘implexicoma‘ which means ‘entwined’. In my experience, Sea Spinach tends to form tighter clumps as it is exposed to the elements to a greater degree than Bower Spinach.
The greatest joy of all three species as a bushfood is that they’re with us all year round, so we may forage for their salty leaves at any time. You can eat the fruit of them too, it’s got its own taste but I don’t think its very pleasant myself. Bower Spinach was is used as a leafy green but you will have to cook it. It’s OK raw but contains a little oxalic acid. The berries of Bower Spinach are tasty and the plant is a source of vitamin C and was used to treat scurvy in the old days.
Use the fresh leaves and stems as a salty, crunchy addition to salads or steam or boil them as you would any leafy greens. If you boil them, a change of water may be necessary due to their high salt content. The berries may be eaten too but are better before they go hard. They can be used to make a red dye too.
Some say that they are better than Warrigal Greens because of their lower level of Oxalic acid. I’ve never measured and compared that compound in them, but it sounds like someone has!