Wednesday, October 29, 2008

A Valiant Warrior

Xanthorrhoea species
When it comes to attack by fire, grasstrees are experts at defence. This fellow has been through quite a battle, as you see, but was still carrying his spear!
Note the little tuft of green on his crown - he’ll be as beautiful as ever in a year or so - perhaps even more beautiful. The blackened trunk which grasstrees acquire after burning enhances their good looks.
There is a story that burning causes them to grow more quickly. Someone I know tried it, and decided it made no difference, so I’m not prepared to take any risks in my backyard.
There is also a story that grasstrees grow extremely slowly - just an inch every hundred years. I’ve had less faith in the theory since I discovered that it was based on a specimen growing in the Edinburgh botanic gardens - hardly the ideal climate for finding out the optimum growth rate of one of our local plants!
These specimens photographed in a railway cutting near Benarkin had obviously been born after 1913, as they were growing on the cut faces, and that is the date that the railway was built. You can see that they have been growing at a good speed, despite the complete absence of any care from a gardener, since then.
You might recognise the plants in the photo below, which can be seen from a walking track in the Bunya mountains. We now think of this sort of rocky hillside environment as being typical for all grasstrees - and indeed it is, for some species.
These plants at the Bunya Mountains are the “white grasstree” Xanthorrhoea glauca. Unusually,  species is also very much at home on the blacksoil plains, something which surprised the explorer-botanist Ludwig Leichhardt.
Sadly, as with most of the native plants which grew on this prime agricultural land, few specimens remain in this habitat, but the knowledge that they grew there is useful to us, when choosing plants for a black soil garden. This is the species to use.

Thursday, October 23, 2008

Native Spinach

Tetragonia tetragonioides
Family: AIZOACEAEThis is a fast-growing, prostrate annual plant which grows very easily from the hard, prickly seeds. It is quite likely just to come up in your garden, as it did in mine, brought by birds, no doubt. It is a nutritious and tasty no-cost vegetable, which, once established provides leafy greens for much of the year with no further help from the gardener. It’s worth putting aside a well-composted space in the vege garden, one or two metres square, for it to ramble and reseed at will. It appreciates a bit of water in very dry times, but doesn’t really need it.
Discovered in 1770 by the botanists on Captain Cooks’ famous voyage, this plant was named by them “New Zealand Spinach”. After leaving New Zealand, they sailed to Australia, and found the same plant growing here. Cook was one of the first sea captains to recognise the scientific discovery that, scurvy was caused by a lack of something - now known to be vitamin C - in fresh fruits and vegetables. The value of this plant as a health food was quickly recognised. The officers tried it and pronounced it “as good as spinage”. (The knowledge that they enjoyed it with a dish of stingray tripe does, I’ll admit, reduce one’s confidence in their taste.) They carried the seeds back to England where it became what is still a popular summer vegetable. Known there as “tetragon”, it is considered to have a flavour superior to spinach and silver beet.
HOWEVER, we do need to bear in mind that, as with all leafy green veges, the right time to eat it is before it flowers. Unless they are being grown for seed, older plants should be weeded out.
Twenty years later, the first white settlers at Sydney Cove were having trouble finding enough food to stay alive. Saturdays were set aside for collecting native plants to eat, especially those which could prevent scurvy. Tetragon was one of the plants collected. It lost favour early on, however. In a colony nostalgic for the homeland, the prejudice in favour of “real English spinach” couldn’t admit that a “weed” from the bush might taste better!
The modern bushfood industry calls this plant “Warrigul Greens”.
Leaves should be washed, chopped (or roll them up and slice them finely), and lightly cooked. Butter, salt and pepper is all that’s needed for a delicious vegetable, but native spinach is also good added to a creamy pasta sauce, included in a risotto, or cooked into a quiche. Another recipe serves it in a white sauce with chopped boiled egg and nutmeg. An imaginative cook will have no trouble finding a good many ways to serve this versatile vegetable!
There have been some concerns about the safety of this plant because it contains oxalic acid, which can be harmful to humans.

How dangerous is Oxalic Acid?A number of Australian plants with edible leaves have high oxalic acid levels, and are avoided for this reason. Taken in excess, oxalates are poisonous substances which can cause nausea, vomiting, corrosion of the digestive tract, and sometimes, death. Frequent use can also cause calcium deficiency and kidney stones.
However, to put the issue into proportion, we should bear in mind that oxalic acid occurs in all green leaves, and that we already eat a lot of plants that are high in it.
The amount contained in native spinach is approximately the same as in “English” spinach, and a little less than in silver beet. Once plants start flowering the oxalate levels in their leaves increase, which is why native spinach (like most of the other leafy greens that we eat as vegetables) is best not eaten after this stage.
Many of the everyday herbs which we grow, or buy in the supermarket, are very high in it. French cooks couldn’t manage without a pot of sorrel (Rumex acetosa), which an internet sales source describes as having “a lemony tang that’s almost as sour as rhubarb”. It’s the high level of oxalic acid that provides the sourness.
It actually takes quite a lot of it to cause harm. Ill effects are typically found only when consumption is very high (more than 12 cups of cooked leaves a week). This is the sort of consumption which occurs in poor, third-world communities where a belly-filling feed is hard to come by.
Some writers claim that high-oxalate vegetables should only be eaten after a cooking process involving blanching them in boiling water for a minute - and this is certainly a way to make them safe, if you think you might be feeding the family too much of it. Most of the oxalates dissolve easily into the water, which is then discarded. Others consider that a certain amount can be eaten safely in recipes where no cooking water is discarded, and salads. The popular spinach quiche would be an example of a relatively high-oxalate meal often eaten in Australia.
A diet high in oxalate-rich leaves should also include high calcium intake, which may offset the tendency to form kidney stones. Typical recipes involve milk, yoghurt, or cheese.

Thursday, October 16, 2008

Necklace Pod

Sophora fraseri
The necklace pods, are flowering beautifully this year, no doubt appreciating the extra rain they had earlier on.
This is a pretty, waist-high shrub with soft silver-green "ferny" foliage and spikes of yellow pea-flowers.
The common name refers to the seed-pods, which fit snugly around the seeds, giving the impression of a string of up to seven beads.
It typically grows on the drier edges of hoop pine vine forests, particularly on basalt ridges. Once common, it has become rare with the clearing of its habitat, and is now listed as a “vulnerable”, plant. You can still find it growing wild on the ridges in the Kingsthorpe area.
It’s a very drought hardy plant (this one in my garden has never been watered), but does grow better in wetter years, and looks more splendid than this if the grower can afford to water it well.
It makes a lovely show if grown with the type 2 darling pea (see article below), as they flower together, and the pink peas fill in below the yellow ones of the necklace pod.

Thursday, October 9, 2008

Who’d Grow Nettles?

Urtica incisa
There are a lot of good reasons for growing this antisocial plant. One is that it is the only host plant for this pretty butterfly, which is an Australian Admiral. When they rest with their wings up, these butterflies are not very conspicuous. This one which I found in my garden last week, wanted to bask in the sun, and did it long enough for me to get this photo. I wondered where it had lived, as a child.
I learned of another good reason for growing nettles from George, on a Toowoomba Society for Growing Australian Plants outing a few years ago.
George was insisting that stinging nettles were a Good Thing in compost heaps, but was a bit vague about the details, so I looked it up on the internet, and found that many people agree with him. Some put the leaves in their compost heaps, or make a compost starter by putting leaves and water in their blenders, then pouring it straight on the heap. There seems to be no general agreement as to whether the effect - speeding up the composting process -is due simply to the high nitrogen content of the leaves, or to some other ingredient.
Meanwhile, other people prefer to apply the goodness of the nettles straight to the garden. The TV show Gardening Australia provided this recipe:
Stinging Nettle Tonic: This plant is high in nitrogen so it promotes good leafy growth. Roughly chop up 1.5 kgs of stinging nettle and then add 4.5 litres of water. In a week or so this mixture will have started to ferment. The liquid can then be used diluted or undiluted as a foliar spray.
That’s two reasons. Here are some more:
3. The roots make a good yellow dye for cloth. Nettle roots were traditionally used in Russia for dying Easter eggs. They wouldn’t have been using our Australian species, of course, but the results are likely to be similar.
4. Nettles have been used as a material to weave into cloth. We’re not talking about any rough old cloth, either! Apparently is it quite silky, and makes better “velvet” than cotton does. It’s also used to make fishing nets, ropes and paper.
5. The tiny seeds can be crushes for their oil, which has been used in lamps.
6. It has some medicinal uses. Curiously, the custom of whipping oneself with nettle leaves was part of folk medicine both in Europe and in aboriginal Australia. The anti-inflammatory effect is supported by modern research, but can be more agreeably absorbed by drinking a tea made from the leaves (which are also high in rich in vitamins A, C, D, iron, potassium, manganese, and calcium..
7. And you can cook it as a healthy vegetable, high in vitamins A, C, D, iron, potassium, manganese, and calcium. Only leaves from the young plants should be eaten. Once the plant has flowered, some substances which irritate the urinary tract develop in the leaves (which probably give the plant its reputation as a powerful diuretic). Apparently it also contains serotonin, that substance which helps us to feel happy. (Serotonin is also found in chocolate, and is supposed to be the source of those chocolate cravings. Eat nettles, and do away with those unhealthy cravings!) The cooking kills the sting, and nettles can be eaten like spinach, or in soup. Try it in a recipe using potato, chicken stock, salt, black pepper, and sour cream.
Not to be confused with the very similar-looking introduced annual nettle Urtica urens, (not actually found in our area, so far as I know) the native nettle Urtica incisa has stems which die back to a perennial rootstock each winter. Growing naturally, they are an indicator of rich soil, so if you’re considering buying a block of land and notice nettles on it, you can buy with confidence knowing that it will be a good place to make a garden.
So those are the reasons for growing nettles.
Of course there is just one reason for not growing it...

Friday, October 3, 2008

Apple dumplings

 Billardiera scandens
My new little apple dumpling plant is flowering already, and it has hardly begun to climb! I plan to keep it in a pot on my patio, where it can ramble about on the the trellis, without making too much of a nuisance of itself. The stems might ramble as far as 4 metres from the base, but are always very fine, and so pretty, with their strong copper colour.
In this country of enormous climbers, it is a relief to find a polite little plant like this - and it’s such a charmer!
The creamy green flowers remind me of 1920's ball gowns, with their handkerchief hems. Despite their colour, they are quite conspicuous, making the plant ornamental.They are rich in nectar, and can attract honeyeaters.
The “apple dumpling” fruits are said to be good to eat. I haven’t tried them, but the story goes that they are delicious when they go soft and yellowish, but completely revolting if tried before this.
The plants can grow in full sun, or in full shade. We see them in grasslands, under established eucalyptus trees, and in the edges of rainforests.
They like all sorts of soils, including heavy clay ones.
They are drought hardy, and can thrive under established eucalypts.