Australia has over 600 species of native orchids which can be separated into two major groups. Terrestrial orchids grow in the ground while epiphytic types are generally found growing on trees. A third group, the lithophytes, grow on rocks and have similar requirements to epiphytes.
About 40% of the species are epiphytic. Epiphytes are not parasites and do not take nutrients from their hosts. Rather, they use the host plant for support.
There are now a large number of hybrids, some with spectacular blooms, others with strong fragrances and some with both. The floral emblem of Queensland is the Cooktown Orchid (Dendrobium bigibbum).
Chiloglottis trapeziformis or Broad-lip Bird Orchid is a small terrestrial orchid with flower stems to about 10cm tall. Each plant has a pair of opposite basal leaves. It produces purple and green flowers during September and November. It does best if grown in containers.
Corybas dilatatus, also known as Veined Helmet-orchid is also small and has veins on the labellum of the flower which end in small points to make a toothed margin. It likes a moist and sheltered situation. It is another that is best suited to container cultivation.
Cymbidium suave is suitable for container planting. It is an epiphyte which forms clumps but the division of the clumps for propagation is not always successful. It produces racemes of olive-green flowers from August to January. The flowers are highly fragrant.
There are a number of the Dendrobium genus that are suitable for cultivation in the home garden. Dendrobium bigibbum or Cooktown Orchid is the floral emblem of Queensland. It is variable species which forms slender clumps. The spectacular flowers appear mainly from March to July and can vary in colour from magenta, mauve, lilac or white.
Dendrobium falcorostrum or Beech Orchid is very popular as a cultivated orchid and does well as an epiphyte or in a container. It produces racemes of highly fragrant, white to cream flowers from August to November.
Dendrobium kingianum or Pink Rock Orchid is adaptable and very common in domestic gardens. It grows well as an epiphyte or in a container. The flowers are usually pink but can be white, purple or various combinations. The main flowering period is from August to November.
Dendrobium tetragonum or Tree Spider-orchid is a very fragrant species with racemes of spider-like, green to yellowish flowers with reddish-purple markings. It flowers mainly from May to October. This epiphytic species is popular in cultivation but can be slow to establish after division or other disturbance.
Diuris maculata is often called the Leopard Orchid as its yellow flower petals have many dark brown spots. It is a terrestrial orchid with flower stems to 0.5m tall. The flowers appear mainly from July to November. It is a striking orchid, suited to cultivation in containers.
Lipparis reflexa or Yellow Rock-orchid is a lithophyte. The racemes bear small, pale greenish-white to yellow-green flowers mainly from March to May. It is adaptable and suited to container planting.
Pterostylis curta or Blunt Greenhood is a small terrestrial orchid with a basal rosette of wavy edged leaves. It flowers from July to October, producing green flowers with red and brown markings. It needs protection from slugs and snails and does best in containers.
Epiphytes can be cultivated on tree trunks or grown on slabs of wood, or similar material. However they are used, they form an interesting addition to any garden.
