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"Orchids for Central Coast Gardens"
The Central Coast has a rich variety of native orchids. Many of these orchids are not difficult to grow and will make a very beautiful addition to any garden. Good local nurseries sell many improved hybrids as well as our local orchid species. Look out for these local orchids when you are out walking in the bush. Observe how they grow and try to copy these natural growing conditions for your plant.
However, do remember that it is illegal to remove orchids or
any other material from the bush.
Reading and talking to other growers will also help you understand the natural habitat of your orchid.
Types of orchids There are two main groups -
- orchids that grow in the soil or leaf litter are called terrestrials,
- orchids found growing on trees and rocks are called epiphytes.
- Most of the terrestrial orchids die down in winter and many of them need special cultivation, so it is more common to find epiphytic orchids available and growing in home gardens.
Epiphytes Attach themselves to their host by-
- growing on the outer bark of a tree,
- clinging to rocks,
- sending their roots deep inside cracks and crevices of trees and stumps. The grassy clumps of Cymbidium suave are an example of this type of epiphyte in our local bushland area.
Growing epiphytic orchids on hosts
Orchids that grow naturally on the outer part of a tree or on rocks can be grown in the garden attached to tree trunks that do not loose their bark. Place a small wad of sphagnum moss on the bark, add the plant and then use a piece of old stocking to hold the plant firmly in place allowing the orchid to establish itself on the host. Using wire or rope around a trees circumference will kill the tree. Using only the outer bark to fasten their roots, these orchids are not parasitic to the host.
Other hosts that can be used to grow epiphytic orchids on are: a block of tree fern fibre, a piece of hardwood such as an old fence paling, dead tree branches or a cork slab. These orchids can also be grown in pots.
Growing orchids in pots
Good drainage is essential. Make sure the pot you use allows ample drainage holes and is only slightly larger than the plant you are potting. Use an open potting mix. A good quality commercial orchid potting mix specially formulated for epiphytes can be used or you can mix your own. Use 70% pine bark and 30% coarse river gravel.
Terrestrials require a potting mix of a good free draining mix such as coarse river sand mixed in equal parts with a sandy loam soil.
Water passes quickly through the root system of orchids growing on trees and rocks in the wild. Water orchids regularly during the warmer months; watering once a week in the winter should be sufficient.
Orchids like good air movement around them. They do not like stuffy conditions which can create fungal problems.
The amount of light needed will depend on the type of orchid you are growing. Many orchid species need filtered light for growing and strong light or early morning sun to initiate flowering. Lack of sufficient light during summer and autumn can often be the cause of an orchid not flowering. Other orchids such as the local Christmas orchid Calanthe triplicata will grow quite happily in heavy shade.
Orchids in the wild rely on decomposing leaves for their nourishment. Orchids need to be fed small amounts of fertiliser regularly during their growing period. They should be well watered before fertilising. There are special fertilisers available for use to encourage orchids to flower.
Healthy orchids are generally not troubled by many pests or diseases. However, slugs, snails, aphids, dendrobium beetles, mealy bug and red spider are some of the pests that can become a problem. Be alert to avoid a population build up. Try to use simple control measures such as squashing or jetting with water, as many chemical sprays can damage the foliage or developing flowers.
Some suggested local orchids to grow
- Iron bark orchid Dendrobium aemulum: is a small species with feathery white flowers. Grow on a slab or attached to the bark of a tree. Flowers September-October.
- Thumb nail orchid Dendrobium linguiforme: is often seen clinging to rocks in moist gullies. Easy to grow attached to a slab or tree. The tiny flower spikes can have 8-20 dainty white flowers which cover the plant.
- Dagger orchid Dendrobium pugioniforme: grows on trees and boulders. Grow on a slab or tree branch. Needs a moist shaded area.
- Rock orchid Dendrobium speciosum: is a robust plant with large leathery leaves found growing on cliff faces with plenty of light. Beautiful showy spikes of cream flowers in August-September.
- Streaked rock orchid Dendrobium striolatum: forms a dense mat on rocks and cliff faces. Grow on a slab or in a hanging basket. Needs good light. Tiny white flowers in September - November.
- Pencil Orchid Dendrobium teretifolium: often found growing locally on Casuarina trees. Creamy white flowers in August-September.
- Tree spider orchid Dendrobium tetragonum: usually found growing in the vegetation along the banks of streams. Will grow in a moist shady position.
- Yellow rock orchid Liparis reflexa: a small plant found on rock faces and ledges. Greenish yellow flowers in autumn.
Other orchids suitable to grow in Central Coast Gardens
Pink rock orchid Dendrobium kingianum: a popular small clump-forming orchid found growing on rocks. Very adaptable, hardy with white or pink flowers in autumn.
Dendrobium x delicatum: an attractive natural hybrid with slender sprays of white, cream or pink flowers in spring. Needs plenty of light.
Beech orchid Dendrobium falcorostrum: has attractive white perfumed flowers. Likes cool, humid conditions. Best grown in a pot with coarse potting mix.
Dendrobium gracilicaule: has long thin canes producing small yellow flowers flecked with brown in spring. Easy to grow on a slab, tree branch or hollow log.
Produced by the Australian Plants Society, Central Coast Group in conjunction with
Gosford City Council and Wyong Shire Council.