I've asked tropicbreeze (Zig) to post some pics of Australian orchids in situ!!

sounds good!

I've managed to get a bit of spare time so I'll make a start on Australian orchids. There are (according to the authorities) about 1400 species of orchid in 192 genera in Australia. In the more southern areas there's a preponderance of terrestrials, with epiphytes (and/or lithophytes) dominating the more northern and tropical regions. In the region where I am there's only about 40 native orchids, which is still pretty good compared to places like Hawaii where there's only 3 native species of orchid.

My local climate is equatorial monsoonal, with two distinct seasons, the wet and the dry. The wet season is wet, humid and hot. The dry season is dry and hot, but nights are cooler. That's why the majority of the orchids here are terrestrials and deciduous. Some live in seasonal swamps where they often go under water. Come the dry season and you won't see anything. Even the epiphytes can lose some of their leaves in the dry. Although, the epiphytes usually flower in the dry season whereas the terrestrials flower in the early wet season and between floods.

This is a current list of our local species (I won't add a list of all the Australian species).

Arthrochilus latipes
Calochilus caeruleus
Calochilus holtzei
Chiloschista phyllorhiza
Cymbidium canaliculatum
Dendrobium affine
Dendrobium canaliculatum
Dendrobium lobbii
Dendrobium trilamellatum
Dipodium stenocheilum
Didymoplexis pallens
Eulophia bicallosa
Eulophia graminea
Geodorum neocaledonicum
Habenaria elongata
Habenaria ferdinandi
Habenaria halata
Habenaria hymenophylla
Habenaria mesophylla
Habenaria ochroleuca
Habenaria rumphii
Habenaria sp. Sand flats (undescribed)
Habenaria triplonema
Malaxis acuminata
Malaxis latifolia
Malaxis marsupichila
Nervilia aragoana
Nervilia holochila
Nervilia peltata
Nervilia plicata
Nervilia sp. Cordata (undescribed)
Nervilia uniflora
Pachystoma pubescens
Phaius terrestre
Phoringopsis byrnesii
Phoringopsis sp. Bradshaw Station (undescribed)
Spathoglottis paulinae
Thrixspermum congestum
Tropidia curculigoides
Zeuxine oblonga

Of the 40 local native orchids I've found 6 growing naturally on my property.

The first is Malaxis marsupichila. It grows along the swampy margins of my creek. Even after getting flattened by flooding when the waters drop, it just curls upright again and keeps flowering.

I have 2 of the Habenarias. This is Habenaria ochroleuca. Grows in wet areas but with less flooding than the Malaxis. Although it does cope really well with occasional flooding.

This is the other Habenaria. I suspect it's Habenaria elongata, but don't actually know for sure. It occupies much the same habitat as Habenaria ochroleuca.

Geodorum neocaledonicum is very common and comes with a few variations in shade of colour. It's often referred to as "weed orchid". It grows in the well drained areas around my garden and also in the not so well drained margins of the creek.

Nervilia holochila on my place grows in colonies along the creek but mostly closer to the edge of the watercourse where drainage is better (when it's not flooding). But it does still get flooded a number of times during the wet season. There's also a smaller colony further from the creek which would be in soggier ground. Close to Darwin (Holmes Jungle) I've seen colonies on the edge of monsoon forest where they get good light but drainage is better. Mine are under tree canopy, but not real dense.

Zig, what a great list and information. 40 orchids is pretty amazing for your area. Ursula and I managed to see each other yesterday and were discussing cymbidiums and where they grow. I mentioned Australia. You make me feel smart! I love imagining my orchids in situ to understand their needs. Thanks so much.
Here are a few pics of Nervilia aragoana and plicata. http://tulear.blogspot.com/sea...

Dendrobium affine is an epiphyte commonly growing on Paperbarks (Melaleuca species) and also a few other species. They also like cycads as mounts. The only thing is a lot of our cycads like fire prone habitats which doesn't go down well with Dendrobiums. I have one that's growing naturally on a cycad but I keep fire off my property.

Breath-taking!

Kathy, there are 3 Cymbidiums in Australia. The most southern is C. suave. C. madidum is in the north east (Queensland) and C. canaliculatum is across the north. They all grow higher up in trees, usually out of hollows in the trees.

I haven't manage to find any Nervilia aragoana or Nervilia plicata in habitat here. I did find Nervilia peltata when I was in central Arnhem Land. When I mentioned it to the herbarium in Darwin they said it was only found on Melville Island, so I sent them some (growing) specimens.

Zig, i have one cymbidium that is a Cymbidium pumilum x Cymbidium suave. It hasn't bloomed since the first year I had it. I let it get cool in fall and winter. Is that appropriate for C. suave?

I suppose it depends on what you call cool. C. suave grows up in the tree tops. From ground level it looks like grass has sprouted in the tree. But up there the temperature wouldn't get as cold as ground level in winter. In the southern parts of Australia they can get frosts in winter but snow is confined to higher altitudes in the mountains,

I had one growing in a hollow log that I gave to a friend. It flowered prolifically and regularly for many years. That friend passed away some years ago and I don't know what happened to the orchid. But it would never have got down to 0C. I don't know what fertiliser it was given.

My cross goes to almost to 0C. Then stays at 13 degrees C for the winter.

Zig,
this is a very interesting thread, with lots of good information! I love the Habenarias! And it must be nice to observe your Cymbidiums in their natural habitat, somehow I would't picture Cymbidium growing epiphytic.

Hey Ursula, you saw one growing epiphytically yesterday, remember? My Cym aloifolium. I can easily imagine it because of that one!!

Yes, that is certainly true!

I dug out some of my photos of a couple of our native Cymbidiums. Can't find the C. suave, might have to do an archaeological dig into my film photos (if anyone here still remembers that ancient form of recording images).

This is C. madidum growing in a Paperbark (Melaleuca sp.) tree. Loaded with seed pods and still flowering.



Flowers



Growing in a mangrove

These are the flowers of Cymbidium canaliculatum. Can't find the photos I took recently of a young plant growing out of a tree hollow.