Sarcochilus australis

A BIT ABOUT . . .  Sarcochilus australis

© Gerry Walsh

Sarchochilus australis flower, green form
Typical plant in situ, olive form

The first thing anyone should say about Sarcochilus australis is that this is one very beautiful Australian native species. It is not “one of your botanicals” as the expression goes. The second obvious point is that S. australis is notoriously difficult to maintain in captivity. It’s reputation for going belly-up is legendary. But I believe it is no more of a problem to cultivate then most other ‘twig epiphytes’, in  particular, other members of the Sarcochilus genus.
There are other members of this genus that I can slaughter with equal panache; S. spathulatus and S. dilatatus are the most likely contenders for the title. And I can throw S. serrulatus and S. parviflorus into the ring with those as well.  My longevity record with S. australis is six years. And I must confess that I doubt the others I’ve mentioned have lasted that long – I don’t really know for sure.
It’s just that S. australis has the reputation and so it’s the one I’ve watched. There are reasons for this dastardly reputation though. The main thing to remember is that S.australis is a very  common orchid. The other four I’ve mentioned are much less encountered in the wild with the exception of S.  spathulatus, which can be locally abundant – but still not as common as S. australis.
Enthusiasts frequently find dozens of plants lying about the floor of a suitable gully. Most cart them off home rather than let them perish wastefully. But inevitably the rescued plants will succumb, with dry skeletal remains in evidence’ all around the bush house. And so it appears to the hapless grower that so many plants have slipped over the brink into oblivion. The conclusion? “This cursed S. australis must be impossible to grow!” I guess it is … but no more so then many of its kin. That’s my theory, anyway.
S. australis is distributed from the Hunter River in Central NSW, southwards into Victoria and across Bass Strait into Tasmania. Isolated plants have been found up as far as the Qld border but it can be considered to be ‘rare’ north of the Hunter. This river separates the vast Central NSW sandstone belt from the rest of NSW. From the moment you cross south over the Hunter into the sandstone country you are likely to see colonies of S.  australis anywhere.

With a few notable exceptions, it continues along southward into Victoria sticking more or less to the eastern coast. The most baffling exception is in the Illawarra. I’ve scratched my head for many years over this enigma. And driven others mad with the inevitable question: “Have you ever seen a single plant of S. australis on the escarpment between the Royal National Part and the Shoalhaven River?” This encompasses a distance of over a hundred kms of awesome native orchid country.

You can find every other epiphytic species that is known to occur south of the Hunter in the Illawarra – with the exception of D. fairfaxii (Blue Mts), D. gracilicaule (Hawkesbury) and S. spathulatus (Wattagans), But no one I’ve discussed the problem with would swear to ever having seen a definite plant of S. australis on the coastal ranges.  In the gorge country around Campbelltown, a major south-western suburb of Sydney, S. australis can be quite common. And it probably occurs in the vast stretches of Water Board catchment high up behind the coastal ranges.

Once you travel down towards Ulladulla and Bateman’s Bay it makes a huge comeback. The escarpment supports some of the finest stands of rainforest in NSW, along with vast sandstone cliff lines that give birth to numerous creeks and gullies. The majority seem indistinguishable from spots just an hours’ drive away which are simply infested with S. australis.

Down in my home town of Kangaroo Valley, I’ve spent most of my life slipping and sliding around leaping creeks,  dank gullies and mossy cliffs. (My father once declared that I would surely turn into an eel if I didn’t return to the sunlight). But that sort of country is in my soul and as a result I’ve seen some incredible sights in my native orchid life. But I’m yet to see a single plant of S. australis in home territory. Why?
It is certainly not uncommon in north eastern Gippsland. On a visit to this region in July 1996, I saw numerous plants, mostly near to sea level, but some at mid altitudes as well. The general environment was certainly similar to S. australis habitat in the Blue Mountains. It is also found in the Otway Ranges, well to the west of Melbourne. I investigated a couple of likely spots but found nothing.
A few miles further along I noticed odd plants hanging from trees beside the main road – usually as we crossed through damp gullies. At another point on a damp ridge top there was one of the largest specimens of S. australis I’ve ever seen – hanging by one root just three metres from the asphalt.
I have been over to Tasmania only once and only for two days. Unfortunately I didn not see any S. australis. However, I believe it is common about the East coast so long as you are in just the right spot. Thereby lays the secret of finding S. australis in the wild. You must be in the right spot.
I have been told that it can be seen if you do a cruise on the Gordon River over on the west coast as well. Apparently it grows on the twigs of trees over hanging the water.What elements does this magic spot possess? I doubt that any person could give a blanket answer to this vexing  question . . .but I’ll have a crack at telling you.

If you are searching the great sandstone regions around Sydney, such as the Blue Mts or the Kuringai area, your colony is 90% certain to have set up home on Backhousia myrtifolia (common myrtle) or Tristaniopsis laurina (water gum).  Virtually every gully in this vast system is choked ‘with one or both of these species. If you are seeing plenty of Plectorrhiza tridentata and Sarcochilus hillii on these same tree species, then you’re in with a chance of findingS. australis among them.

On the myrtles you’ll no doubt be seeing a good few specimens of Dendrobium aemulum as well. Water gums right in or lining the banks of creeks do often hold huge colonies of S. australis. But I believe myrtle to be a much more common host tree. They won’t necessarily be hanging over running water either. You could be just on that fringe line between cool myrtle gully and dry sclerophyl type bush beside it.

Such gullies usually only require two or three steps for a searcher to pass from one environment into the other. Another species that commonly holds good numbers of S. australis is a kind of rambling, prickly shrub that often lines dry, grassy gullies in steep country, and of which I have no idea what it’s real identity could be. It may be Blackthorn.
lt has thorns around one cm long and virtually always has dry moss and that old man’s beard moss all through itsmessy branches and particularly on the match thick twigs. But S. australis does occur sparingly on a wide variety of other hosts within the major environments discussed.

Then again you may be under a canopy of Coachwood rainforest, or other typically rainforest type tree species. Here you’ll find plants on the twigs that fall from high up in the canopy. S. australis is a common orchid, but do not be deluded. You could expire from old age while searching out your first colony! I cannot think of another species that sets up private enclave quite as selectively as S. australis does. Its an absolute snob.

While stumbling about a likely gully, you may not see a single specimen of S. australis. Within metres you could be staring dumb-stricken at hundreds of plants. And while you’re doing a Cherokee rain-dance at your long overdue success, you may take a couple of steps too far and lose sight of the lot in the blink of an eye.

I don’t think I’ve ever seen a colony that extended beyond fifty metres or so along a creek. To the eye, conditions appear to be identical within and out of the colony. Another hundred metres away you could very likely walk into another big colony. Or you may not see any more for the rest of the day.

No doubt you’ll be seeing plenty of other native orchids along the way. While some colonies can be measured by the hundreds of plants, most seem to consist of just a few dozen specimens. I doubt there could be any other reason for this quirky selectiveness other than the presence of a suitable fungus for seed germination.

As I stated before, S. australis is a ‘twig dweller’. It mostly seeks out little branches and even vines that are thinner than a broom stick. Plants are often seen on wood no thicker than a match. Their roots will travel for over a metre along such thin twigs and when several roots join up and travel together the host twig is often camouflaged.

S.australis will fairly often attach itself to much thicker trunks and branches up to 15 cms wide.  And when it does so, this species can grow into quite a substantial size. I have seen single lead plants 25 cms across with a dozen leaves up to 13 cms long and 2 cms wide. I stress that this is exceptional.

An average plant of S. australis would only have three or four leaves of perhaps 5 to 8 cms length. The majority of plants in a colony would be much smaller than the average however. For S. australis appears to be a very fertile species that produces lots of offspring. Young plants flower at amazingly small sizes – 20 cent piece size.

Racemes on such tiny plants rarely support more than 2 flowers however. S. australis has even been known to flower while still in the flask. Average raceme length is non-existent with S. australis. Anything is possible right to the upper limit of 22 cms or 9 inches. This may sound outlandish to novice growers but it is true.

Last November I was amongst hundreds of flowering plants in the Megalong Valley and some racemes were around 18 cms long, many were over 12 cms and all the others got randomly smaller until seedlings only sprouted the single flower.

Nothing seemed to be an average at all. S. australis will kieki only infrequently but when it does it can throw up a dozen or so racemes. Single lead plants often have two racemes on board even smallish plants. Flowers are quite variable. Some are up to an inch deep while others may be half this. Some are squat and nearly wider then deep.

Colour is a lottery. The two basic background colours of the segments are bright but light green, and light brown/tan. The large labellum is usually snow white with red striations on the side lobes and a deep purplish spot on the mid lobe. Sometimes there is also a purplish spot on each side lobe. In the Blue Mts, plants are flowering at their best from November right up to Christmas.

So now you want to know how to grow this delightful species I guess? Well don’t look at me too hard. The plant that lasted six years for me was tied onto a strip of iron bark totem and the roots eventually reached around 30 cms long. Like all the Sarcs that drop dead with SSDS (Sudden Sarc Death Syndrome) it all relates back to the crown. That’s where they die. I don’t think there is a cure or a preventative.

I’ve also had success for up to three years by attaching smallish plants to thin lengths of bamboo with a few strands of epiphytic moss hanging loosely over them. The roots romp away over the shiny surface and attach very well. But the crown will one day rot out. This seems like a good time to sprout off a bit of philosophy on conservation and the ethics of taking plants out of the bush etc.

S. australis is not programmed to last long. In the wild it germinates in great abundance, it grows roots from the protocorm with surprising speed and flowers from tiny plants. It does this because it mostly germinates on thin twigs that often die and fall to the ground in short time – with the orchid on board life is designed to be short for S. australis and it lives life to the full and generally dies young.

Unless you’ve explored a large colony and seen the high number of plants that lie on the ground or are already dead from doing so, you probably won’t go along with what I’m preaching. But I see no harm in picking up these plants and having a go at extending their life. If plants have seed pods on board, and they often do, I prop them back up in a suitable limb so that seed dispersal will proceed at least one more time in the orchid’s life.

With this approach I only refer to those twig epiphytes that are doomed. Don’t be an idiot and take secure plants. The little ones inevitably establish quicker and last longer than the big specimens do anyway. Be happy with windfall plants and let the rest live on. You’ll feel very satisfied with your self-control once you get the evacuees up and growing, either in yours or in a friends bush house.

I believe that native orchids, the epiphytes at least, and in NSW at any rate, are probably in very good shape conservation wise. Think about it, forty years ago there were nurseries all over the place selling them. Particularly around the North Coast and the Mid North Coast. Just in Sydney there were three large nursery outlets that advertised native orchids extensively. You could buy just about any species you wanted.

You can’t do that nowadays. In 1983, rainforest logging was stopped in NSW. This virtually dried up the supply in short time. You still see odd species for sale here and there – especially in the big chain stores. Qld was supposedly the source of all the plants. It does seem like that state was way behind the rest.

Things aren’t like they were in the bad old days of the seventies and early eighties. Back then all the orchid society members mainly grew bush collected species. And the government gave licenses to nearly anyone who wanted to get in on the act.

Today in a native society like ANOS Sydney Group, there probably wouldn’t be more ten dinosaurs who still go out to the bush to see orchids in situ. Everyone grows species from flasks and now our benches are festooned with around 75 hybrids at shows and meetings. This is a good thing.

You can’t tell me that there is anything like the vast numbers of orchids coming out of the wild today that there was just that short time ago. But still some people beat their drums and rattle their swords when they hear of someone going bush for a few days.

There is an automatic assumption that people like myself are intent on sweeping through the back blocks like a swarm of plague locusts. It just ain’t like that dear reader. I have digressed far enough. Back to the real world. Just be honest and conserve our native orchids because, like I’ve said before, they don’t grow on trees . . .