SHOWY SPECIOSUM

A very popular orchid grown in culture in South Australia is the epiphytic/lithophytic Dendrobium speciosum.  It is a showy species with a heady perfume.

Dendrobium speciosum
Dendrobium speciosum (Rock Lily, Rock Orchid) in culture

This species ranges along the eastern seaboard from Queensland just peeking into Victoria.  There are nine variations each with its own unique distribution.

Map source The Rock Lily Man

But not only is it popular in South Australia, it is popular throughout the country.  The whole of the 2006 September issue of the Orchadian was devoted to a single article on D. speciosum.  The March 2016 Orchadian has three articles plus references to D. speciosum in other articles.

And then there is Gerry Walsh who is so passionate about this species that he has a comprehensive website – The Rock Lily Man – devoted to it.  Explore and enjoy his website.

 

Calliope Range, Sept 2005
Photo source The Rock Lily Man

The Orchid Club of South Australia has produced a fact sheet for growing this species in South Australia.

 

 

Advertisements

Growing Dendrobium kingianum in Adelaide 1983 and Now

In 1983, Ron Robjohns, NOSSA’s first treasurer, wrote a comprehensive series of articles about growing epiphytes in South Australia. Thirty years on Ron’s information for growing is still helpful and applicable for today. Any updates or extra information are in black text.

NATIVE ORCHID SOCIETY OF SOUTH AUSTRALIA JOURNAL Volume 7, No. 3, April, 1983

GROWING EPIPHYTIC ORCHIDS IN SOUTH AUSTRALIA – R.T. Robjohns

Dendrobium kingianum (Pink Rock Lily)

This is possibly the best known and most variable of our native epiphytic orchids. Its range is along the coastal strip from the Hunter River in New South Wales to Rockhampton in Queensland. While it is principally a lithophyte and found growing in large mats on exposed rock faces, it is also found in shady gullies and on trees.

It has three to six lanceolate leaves up to 13 cm long on stems varying from slender stems, pseudo bulbous only at the base, to short stout pseudo-bulbous stems. The pseudobulbs are usually 8 to 10 cm long with some up to 30 cm in length; the colour varying from pale green to dark reddish green. One to three racemes of up to twelve flowers, often fragrant, are borne from the top of the pseudobulbs, the colour, while commonly pink, varies from white to purple. They are up to 25 mm in diameter having the labellum usually spotted and blotched with mauve. The flowering season is August to November.

It can be grown on slabs or trees (e.g. Jacaranda or Melaleuca) but locally, best results are obtained from pot culture – rafts or hanging baskets, using an open mix. Some growers use a commercial cymbidium mixture.

I have had good results by lining wire baskets with a thick layer of live spagnum moss and filling them with small pieces of seasoned pine bark and charcoal. I find that the plant not only grows up but also out of the sides of the basket.

Some shade is required in our summer I have had success using 50% shadecloth. Protection from our winter frosts is also necessary. Fertilise lightly in the growing season using commercial fertilisers at half strength.

Being hardy it is well suited to cultivation and hybridisation. D. x delicatum is a natural hybrid of D. speciosum and D. kingianum, also D. x suffusum is a natural hybrid of D. gracilicaule and D. kingianum.

A number of man-made hybrids are available. Some of the best known are D. Bardo Rose (D. kingianum x D. falcorostrum). D. Ella Victoria Leaney (D. kingianum x D. tetragonum), all of which respond well to pot culture and flower freely.*

Propagation is either by division or cultivation of “keikies”.

Drawing of Dendrobium kingianum
Drawing of Dendrobium kingianum

*The number of hybrids has increased since 1983.

Growing Epiphytic Orchids in Adelaide 1983 and Now

In 1983, Ron Robjohns, NOSSA’s first treasurer, wrote a comprehensive series of articles about growing epiphytes in South Australia. Thirty years on Ron’s information for growing is still helpful and applicable for today. Any updates or extra information are in black text.

NATIVE ORCHID SOCIETY OF SOUTH AUSTRALIA JOURNAL

Volume 7, No. 3, April, 1983

GROWING EPIPHYTIC ORCHIDS IN SOUTH AUSTRALIA – R.T. Robjohns

Epiphytes usually grow where there is plenty of air movement, ample light but also shade and to achieve this they are frequently found well above the ground storey in the forest from where, should they be dislodged from their host and fall to the forest floor they wither and die. With most plants the roots grow downwards, however, with epiphytes in their natural habitat, the roots may grow up, down or around their host, that is, in any direction in search of suitable conditions.

As a novice grower I urge you to learn all you can about the natural habitat of the plant and its principal host, bearing in mind that in accounts of plants that grow on rock faces, often they are growing with their roots in crevices into which any moisture drains and maybe in an accumulation of leaf litter. Frequently the rocks on which the lithophytic orchids grow are sandstone – a rock which can absorb moisture and consequently keeps cool longer than most other rocks. “In an exposed situation” should not be construed as being in full sun all of the time: usually they receive some shade.

With the possible exception of Cymbidium canaliculatum few epiphytes grow at their best in full sun in nature. Full sun in the hot dry South Australian summer will usually burn off the plants or at the best cause severe yellowing and loss of leaves. It is to be noted that this State has no native epiphytic orchids.

Most Australian epiphytic orchids grow in the coastal belt of northern New South Wales and Queensland where the average rainfall in their DRY season is much the same as the Adelaide winter or WET season with which it coincides, consequently advice that plants require to dry out during the winter should not be taken to the extreme and the plants left without water.

The three principal requirements of epiphytes are a free air circulation, a semi-shaded position and free drainage.

In South Australia epiphytes are grown in two ways, the most popular being pot culture and the other slab culture.

For pot culture the medium must be a free draining one and a mixture of “aged” pinebark, scoria and charcoal is quite effective.

Note 2015 – Today the potting media used is composted pine bark.  Charcoal is not used and scoria can get cold and wet in winter.

In choosing material for slab culture consider the conditions under which you intend to grow the plants. For humid conditions cork is ideal while tree fern, which holds moisture longer, is good for dry conditions, although any of our native trees with papery or corky bark is suitable. Perhaps you would wish to attach the plants directly to trees in your garden, for this purpose try Jacaranda, Melaleuca or trees with a similar bark.

Watering is important, slab culture requires more watering than pot culture and in summer water orchids on slabs at least every second day and every-day during a hot spell. Water according to the weather and watch for signs of stress – in wintertime the rain is usually sufficient.

Fertilising is best done using half of the recommended strength of commercial proprietary fertilisers.

As a last general recommendation – beware of frosts. Last year (1982) the frosts in some areas of Adelaide caused severe losses amongst plants of epiphytic native orchids. Large tubs of D*. speciosum, whose thick leathery leaves I mistakenly thought frost resistant, were reduced to a mass of leafless canes; even baskets of D. kingianum hanging three feet below the 50% shadecloth had all of the leaves burnt off. These were but two of the varieties which suffered, so be warned and ensure that your plants are protected from frosts.

*D. = Dendrobium

Dendrobium speciosum
Dendrobium speciosum in culture

 

Australian Orchids & the Doctors They Commemorate Part 16 of 20

Hereward Leighton Kesteven (1881 – 1964)

A general medical practitioner, medical scientist, zoologist, pioneer of industrial medicine in Australia, and national medical director of the Allied Works Council during World War II.

Orchids

Dendrobium kestevenii  is the name applied to the hybrid between D. speciosum subsp. speciosum and D. kingianum

Confucius’ thoughts on Orchids

Confucius was an admirer of orchids and in this quote he captures the quality of the epiphytes in this eloquent translation*:

The orchid grows where others cannot enduring the hardships of hunger and thirst, and is loosely tied to the things that support it.  And, even with all the difficulty of its life, the orchid graces the world with beautiful colour and rare fragrance.  This is like the life of the true gentleman, who sets himself to learn self-discipline, and whose character shines no matter where he is or what he experiences.

Though he never saw an Australian epiphytic orchid, the description holds true as can be seen in these three pictures from among the many species found on the eastern seaboard.

Sarcochilus falcatus
Sarcochilus falcatus (Orange Blossom Orchid)
Dendrobium speciosum
Dendrobium speciosum (Sydney Rock Orchid)
Dockrilla linguiformis
Dockrilla linguiformis (Tongue Orchid)

 

 

 

 

 

 

*From The Fragrance of the Unread Poem by Jonathon Steffan http://www.jonathansteffen.com/the-fragrance-of-the-unread-poem/ Accessed 10:04pm 30th June 2014