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 plant that forms patches of up to 3 m
Flowering Time: All year
Kaurna name: Pirira
Description and uses:
Bower Spinach (Tetragonia implexicoma) and Sea Spinach (Tetragonia decumbens) are local relatives of the well known Warrigal Greens or New Zealand Spinach (Tetragonia tetragonoides) that restaurants love.
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.
Both species are easy to find, sprawling succulents (see below). Both have shiny leaves. Bower Spinach likes cooler, moister soils under trees near beaches and in the Mallee. Sea Spinach prefers more open places such as on dunes. They are vigorous, sprawling, scrambling herbs, frequently with stems that are metres long that can cover rocks and shrubs.
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.
There is another, similar plant that isn’t so common this way, that is Coast Twin Leaf which only flowers early in the year and has much larger leaves that are duller than Bower Spinach.
The easiest way to tell them all apart is as follows: Both have 4 petals but Sea Spinach has many anthers and Bower Spinach only a few anthers. That’s my general guide.
Both have reddish stems when young that get darker and browner with age. They frequently measure in the metres, lengthwise. Bower Spinach stems become woody as they get older. The leaves are green, thick and succulent and covered with little bubbles of salty water.
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!