Tag: Growing Orchids

Gleanings from the Journals: Dockrillia linguiformis 2006

This week’s blog is an extract from Volume 30 No 10 November 2006.  In this article of Len Field he gives not only cultural notes but also some interesting background including an orchid link with the infamous Captain Bligh.

Dockrillia linguiformis (Sw) 1800 Brieger

Dockrilla linguiformis
Dockrilla linguiformis

Len Field
Common names Thumbnail orchid, Tongue orchid, and in North Queensland the Tick
orchid.
The name linguiforme is from the Latin lingu(a) as in linguiforme (a tongue). It was also claimed for many years that this was the orchid that Olaf Peter Swartz the German botanist founded the genus Dendrobium in 1800, but this was wrong, although this was the first orchid seen by white man when they landed at the rocks area in Sydney cove, Port Jackson.  It was introduced into England by Rear Admiral Bligh of Bounty fame.
Other names it has been called are
Dendrobium linguiforme var. linguiforme Swartze 1800
Callista linguiforme (Swartze) Rev. Kuntze 1891
Dendrobium linguiforme (Swartze) var. huntianum Rupp 1942
There was another variety named from this species called var. huntianum by Rupp in 1942, which was named after T.E. Hunt and is a June or July flower and found near Ipswitch (sic) in Queensland, but as it reverts to type form it never reached true variety status and was considered just a variation of the type form.
This orchid has a huge range of habitat which stretches from almost the Victorian border up to North Queensland and West to the Great Dividing Range. It is very common throughout this area and equally happy as an epiphyte or a lithophyte but where as a epiphyte it likes swamp oaks (Casuarina glauca), river oaks (Casuarina cunninghamiana), in fact it will grow on most trees that will hold there bark including the tea trees (Leptospermum species).  I have seen this orchid hundreds of kilometres inland from the coast still forming large mats on the rock faces, while in its more prolific growing areas these mats will cover huge areas of the rocks where it can survive and grow in extreme exposed conditions that would kill other orchids. In the dry times the leaves which are very thick, tough and numerous will shrivel and can last up to six months without water. This is a feature of a lot of Australian Dendrobium and Dockrillia
Flowering is from August to October with blooms that are long lasting, up to two weeks with one raceme per leaf.
Culture. If grown on slabs which is the usual way it should be hung up high and if grown in pots a very coarse open mix. In nature it likes plenty of sunlight although at times it will grow in shade. Whichever way it is grown it should have good light, humidity and air movement.

Den linguiforme drawing
Dendrobium linguiforme


Why use a mulch on your potted terrestrial orchids?

Here in South Australia, it is very common to see a covering of She Oak needles (Allocasuarina sp.) on pots of terrestrial orchids.  According to Les Nesbitt, NOSSA founding member and experienced terrestrial orchid grower, there are four reasons for this

  • It keeps the leaves up off the soil.
    • Provides good air circulation
    • Helps prevent leaf rot.
  • It provides nutrients to the fungi
    • This is very important for the fungi dependent orchids.
  • It stops pitting into the soil when it rains.
    • This is most likely to occur when pots are under the drip line of a shade-cloth.
    • Pitting exposes the root system.
  • It allows the leaves to readily come through because of its small diameters.
    • Other mulches, such as gum leaves, smother seedlings.

She Oak needles are the choice of mulch because it is

  • Long lasting and takes more than year to break down
    • which means that it lasts the whole growing season.
  • Does not become mushy or spongy
    • unlike pine needles and grass cuttings which breakdown more quickly into a wet soggy mass and contribute to leaf rot.

It should be noted that it is necessary to replace this mulch yearly.

These two pots were in the same area under the shadecloth. Notice the damage to the pot without the mulch.
These two pots were in the same area under the shadecloth. Notice the rain damage to the pot without the mulch.