Thursday, November 27, 2008

Austral Cornflower

Rhaponticum australe (Stemmacantha australe)
I was astonished to hear that this rare and threatened plant had been found growing on a neglected block in Toowoomba a few years ago. It must have been the last city refuge for this plant, though it would once have been common here. It used to be found on our local red ridges and blacksoils, wherever those very common local trees, mountain coolibah (Eucalyptus orgadophylla) and narrow-leafed ironbarks (E. crebra), are found. In town, gardeners usually mistake it for some kind of milk thistle, and weed it out. In the country, the livestock have done the job instead. So plants growing wild are now very rare indeed.

It is one of those native plants which you’d have to classify as “almost ornamental”. Planted in quantity their spring flowers do make a rather attractive garden statement, with their globe-artichoke-like heads.

Their light brown seedheads have an almost animal appeal. I find myself wanting to pat them on the head like little lambs.
In fine weather, the seedheads are long-lasting. However,  they don’t stand up well to rain and wind, and soon look messy in poor weather. A firm hand with the secateurs is needed to keep the garden looking pretty.

A few heads should always be saved for seed, of course, and they’re easy to reproduce this way.

For those who have enough land to be able to afford some “rough”, this is a good plant to naturalise there, as it provides food for little birds and herbivores.

Stout Bamboo Grass

Austrostipa ramosissima
This is an ornamental grass which grows along the slopes of Great Dividing Range in the Toowoomba region, on red soil.
 It makes an excellent quick hedge, with the plants lasting about three years before they get shabby. Removing the old plants is simple, as they are shallow-rooted clumps. If done in spring, this allows self sown seedlings to grow up i their places. (Older plants lose their vigour if they are cut back at all, so rather than making any attempt to refresh them by cutting them back, it is better to remove and replace them.)

Like so many of our lovely Australian plants, this one is more highly valued as an ornamental garden plant overseas, than in it's home country. In the US, it is known by the delightfully appropriate name of "Pillar of Smoke".
It is frost and drought tolerant.
I find it problem-free, despite its self-seeding habit. Unwanted seedlings are easily removed by hand or killed by mowing.
Like all native grasses, it is an environmentally friendly thing to grow, providing food for small birds and insects, and shelter for small animals.

The tall stems, with their generous spring panicles of very fine seeds are also rather good in a vase. A few Christmases ago, when I was feeling rather arty (and had no grandchildren to amuse) I used a few stems of this grass for a Christmas tree. I decorated it with Christmas earrings and tiny baubles, and was rather pleased with the result!

Saturday, November 22, 2008

Native or Not?

Papaver aculeatum
I was delighted, a few weeks ago, to find a “native poppy” growing beside the Mt. Kiangarow track at the Bunya Mountains.
I had not previously found it growing on a relatively unmodified site on basalt soil, so was pleased to find out that it seemed to be a genuine local.
Alas, my subsequent research revealed that this may not be so!
Trawling the internet, I found a very good article by Tony Bean, of the Queensland Herbarium, on his new system for deciding the probable status of plants, like this one, whose origin is disputed. He puts together a very convincing case that our “native” poppy is native in South Africa only.
I have been happily growing it in my garden for years, and will go on growing it. Actually, it would be difficult to stop growing it, as it reseeds itself every year. I’m happy for this to happen, as it is an attractive plant whose spring flowers add a touch of an unusual shade of scarlet to the garden
But I’m disappointed.

Yellow Marshwort

Nymphoides crenata
What a silly little plant this is! It doesn’t like the container I’ve put it in. It’s too shallow for it, and there’s not room for a good layer of deep, rich mud, which is what it would really like. So it has responded by shrinking its leaves, as it does in the wild when times are tough. It seems to be telling me what a mean old gardener I am.
So I didn’t expect it to flower so happily, with normal-sized flowers which are bigger than the leaves.
In better conditions - still (or slow-flowing) fresh water to 1.5m deep, with a muddy bottom - the leaves are about 12cm long.
This plant dies back to almost nothing in winter. Fresh new growth appears every spring, and spreads across the water by stolons (like those on strawberry plants). Flushes of flowers appear every few days from November to about May.
Like strawberry plants, they are easily reproduced from the plantlets which appear at each node.
This wavy-leafed marshwort is plant of the inland, but is now often seen east of the dividing range, having been introduced there by gardeners. Apparently they like the wavy-edged leaves of our sort rather than the smooth-edged ones of their local native, the very similar Nymphoides geminata.

Sunday, November 16, 2008

Who’s been eating my Mosquitos?

Yellow Bladderwort  
Utricularia gibba ssp exoleta (Utricularia exoleta)
A little bird gave me some of these lovely plants for Christmas. Literally.
They appeared in the Gardner pond one year.
For some time, I paid no attention to the plant, which was just a mass of fine, entangled green stems, with no obvious beginning or end, top or bottom, roots or leaves. It was peppered with little black lumps, smaller than a pinhead, and floated submerged, neither very attractive, nor particularly unattractive. When the first flowers appeared in a shallow corner I was slow to connect them with the floating plant.
They were very pretty, bright yellow, measuring a centimetre across, and standing 6cm above the water on fine little stems. I was charmed by them, but had considerable difficulty making an identification. When I eventually discovered what the plants were, I was delighted to know that this is one of the world’s more sophisticated carnivorous plants!
The “black lumps” were the bladders, which provide the plant with enough nutrients for it to be able to live in quite nutrient-poor water. I’ve discovered that they are very effective at keeping my bowls of water-plants free from mosquito larvae. They don’t get rid of visible wrigglers, but water with this plant in it remains wriggler-free, so it must be consuming them fresh out of their eggs.
Some research told me that the bladders in “hunting” mode are rather flat, with a little round entrance above which a few trigger hairs protrude. Nearby glands secrete a sugary bait. If a tiny creature touches the hairs, the bladder springs into its full ball-shape sucking in water and the prey. The door snaps shut, and the water in the bladder is pumped out again through some little glands (taking 30 minutes to 2 hours). By then, the bladder has returned to the flattened shape, and opens its door for more prey.
Meanwhile, the previously-caught prey is slowly being digested to feed the plant. Bladders which have fed successfully are black, and I notice that my plants’ bladders don’t have much luck in winter, when I suppose the bladderworts have to live on photosynthesis alone.
Apparently mosquito larvae and even fish fry can be captured by the larger bladderworts – and the little dots on my plants seem to be large by bladderwort standards. They don’t seem to bother the goldfish or frogs. (I have no native fish, so don’t know whether these are affected.)
Although these bladderworts can live in fresh, still water of any depth, they need shallow water to flower. The water’s pH should be 6.3 to 6.8 - rainwater is fine. A ledge at the edge of a pond, or a dish or bowl part-filled with soil or sand seems to suit them, and a warm, sunny site (they like to be between 18 and 29°) keeps them flowering well, but they survive the winter so long as their water doesn’t freeze.

How to “Source” Bladderworts.

Acquiring some for yourself may be a simple matter of providing a suitable habitat, and waiting for the birds to provide. I have a rather large birdbath, in which I’ve put some sandy soil which slopes from just above water level to 5cm deep, so plants can choose their own depth.
Other gifts from the birds have taken root on the higher soil, making a healthy little ecosystem and a very pretty garden picture. Magpies bathe in the deeper water, but this doesn’t worry any of the plants in my pretty dish-full.

Other Gifts from the birds.
We have never been able to stop the drips from the solar hot water system on our roof. The people from Solarhart assure us this is normal. I hate letting it go to waste, though, so have a birdbath/water garden underneath it, which I only need to top up with rainwater in very dry weather.
It now has four lovely thing growing in it, all bird-given.
Triangular Club-rush, Schoenoplectus mucronatu
This elegant “decorator” plant it is so good to cut for a vase when it’s in flower (Sep - May). The light green triangular stems can get to 50cm high, but are much less in the restricted soil of my bird-bath. 2cm from their tips they put out - sideways - a neat bunch of their little flowerheads - the golden-brown cone-like “clubs” which give them their name.
Left to themselves in a pond or dam they form a thicket in the shallow water and provide good breeding sites for frogs. Though they seed freely, they are not particularly invasive. In my own dish, I find a once-a-year (early spring) clean-out and re-plant keeps the arrangement looking good year-round.

Trailing Pratia, Lobelia pedunculata (Pratia pedunculata)
I am unsure whether this plant came to me from a native source, or from a garden, as I am not aware of it as a wild plant in the area.  It as it is an easy native plant to buy, and mine is a lovely (commercially desirable) shade of blue, so perhpas it's not a real native. On the other hand, water plants tend to have a very wide native range, so perhaps it can qualify as a valid addition to this blog about local native plants..
The plant needs constant dampness for success in full sun, and rewards us for providing it with a generous sprinkle of its blue flowers from October through to April.
It’s said to tolerate light frosts.

Small-leaved Pennywort, Hydrocotyle peduncularis
You see this one on lists of plants recommended for frog-gardens. It has dainty little (1cm) leaves, almost circular, with five scalloped lobes. They make a pretty carpet of soft, fresh green at the water’s edge (both in and out of the water), and mix happily with other small plants such as Lobelia and Utricularia.

Friday, November 7, 2008

Plover Daisy

Leiocarpa brevicompta (Ixiolaena brevicompta)
I have no idea why this plant is called “plover daisy”. Perhaps it’s because spurwing plover (also called masked lapwings) nest amongst the plants. I’m sure we all know this common local bird, which nests on the ground, and defends it vigorously by dive-bombing us and shouting “ack-ack-ack... “
It’s a pleasing mental image, the yellow masks of the plover among the soft, woolly blue-green leaves and the yellow flowers of its namesake daisy.
This is a rather variable plant, with Australia’s best version, having the most generously woolly foliage and the largest buttons, occurring naturally on blacksoil in a strip between Drayton and Cambooya. It occurs in other parts of our area, but so those wishing to grow it might prefer to source their plants from the right spot.
Like the prophet, it is little valued in its own country, and we rarely see this plant in gardens despite its obvious desirability. It is particularly good with a cottage-style garden and has that style’s traditional easy-care qualities, being a frost and drought-hardy biennial, very easily grown from seed. The plants are easy to find at present as it is now showily in flower around the district. Once established it self-seeds fairly easily (particularly if the garden gets a little cultivation and water), the seedlings appearing in spring. It would be very suitable for sale in punnets, as a bedding annual
Self-sown plants have growth spurts in spring and autumn and look their best if cut back twice a year to keeps the plants neatly shaped, and encourage regrowth of the woolly blue-green foliage.
A warning to graziers is appropriate, however. Though this is a useful fodder plant before it flowers, its seeds can poison sheep. The Queensland Dept. Of Primary Industries has noted that there have been deaths from this cause in Western Queensland when the plant is eaten in problem quantities, (which they define as 50% or more of the total diet, for 1-2 weeks). They suggest these management strategies:
I. Stock pastures heavily while the plant is still green, to reduce seed-set.
2. After seeds appear, let each mob of sheep graze on the pasture for a week only, once the seedheads mature, then replacing them with a different mob. Apparently the sheep actively seek out the seedheads to eat, and DPI regards this as a safe way of reducing seed numbers.
Based on this, I consider that this is not a plant we need to avoid for fear of causing a poisoning disaster.
Where we see it naturally occurring in pastures here, the proportion is always relatively small and does not seem to become dominant even with overstocking - though perhaps others may report a different experience? The seeds are not wind dispersed, and self-seeding in my garden has only ever occurred very close to the parent plants.
Too many good native plants are avoided, with the potential to slide quietly into extinction, because they have been discovered to be toxic to stock. The word gets around that they are poisonous, and people tell each other not to grow them without first establishing to what degree they are really likely to be a problem. That stock feeds mainly on Australian plants means that they have (rightly) been the subject of much research and some publicity. Meanwhile, many very commonly grown introduced plants, some of them really dangerous to children, appear in our gardens without comment.