The majority of people usually start cultivating orchids by attaining a Cymbidium first. These have big fat bulbous growth at the base of the plant. They are not true bulbs but are called pseudo bulbs which are storage organs to help the plant through lean times. The pseudo bulbs are topped by several straps like leaves and the flowers appear from the base of the bulbs.
WHAT MAKES AN ORCHID DIFFERENT FROM OTHER PLANTS?
Orchids differ from all other flowering plants in numerous ways, the main one is in their reproductive apparatus. In other flowers such as daisies, roses, lilies, etc., anthers, which carry the pollen and is the male part of the flower, is separate from the stigma which is the female part and receives the pollen. In the orchids these parts are fused together in an organ called the column. The pollen of the orchid is not dust-like as in other flowers but is in 2-4 sticky, waxy globules called pollinia. These are situated at the top of the column and transferred mainly by the insects, seeking nectar, to the lower section of the column which has a sticky recessed section called the stigmatic plate, thus effecting pollination.
Another significant difference is that orchid flowers are zygomorphic meaning that when they are split into two equal halves on one plane only, the parts are of identical appearance. Most other flowers can be split into two equal halves on any plane and still be identical.
There are diverse differences but these are the principal two.
THERE ARE MANY DIFFERENT ORCHIDS.
The number of different orchids throughout the world has never been determined with any accuracy.
Estimates range from a low of 20,000 to a high of 35,000 species. It would seem that a figure of approximately 25,000 valid species is a safe and reasonable estimate.
In addition to the 25,000 or so wild orchids, there exists about 60,000 hybrid forms, this number increases by over 1,000 each year.
Thus in the Orchidaceae we have by far the larger number of flowering plants known to science. At the lowest estimate something in excess of 80,000 at the present time.
WHERE DO ORCHIDS GROW?
Orchids in the wild can be found growing all over the world with the exception of the Polar regions. The greatest accumulation being in the tropical and sub-tropical regions of South and Central America and in New Guinea.
Australia is not rich in native orchids having about 660 species many of which are unique and not found anywhere else in the world.
HOW DO ORCHIDS GROW IN NATURE?
There are basically two types of orchids: (1) Epiphyte and (2) Terrestrial
In Greek Epi means on top of' and phyte means plant therefore Epiphyte means a plant growing on another plant. Contrary to some beliefs they are not parasitic. They just use other plants to perch on. Most of them grow high on trees in forests where the light at ground level is too low for survival. Most of the orchids seen at shows are Epiphyte. Many are very showy with large colourful flowers.
Terrestrial, as the name suggests, grow in the ground similar to many other plants. Terra means earth, soil, ground, land, etc. The majority grow in the cooler regions of the world where they arise from an underground tuber much like a soursob. They are dormant during summer months when they are quite deciduous, putting up new growth in late Winter and flowering in the Spring. Some species grow in the tropics and sub-tropics and are mostly evergreen. As a general rule the terrestrials are not as showy as the Epiphyte but like all things there are exceptions.
GROWING ORCHIDS IN CULTIVATION.
Just like most other types of plants some can be very easy to grow, some a little more difficult and some are impossible.
Here in South Australia we have a climate ideally suited to growing many species and their hybrids if certain conditions are provided.
Ideally a structure with a covering of 50% shade cloth is desirable but not absolutely necessary. A collection of a small number of plants can grow and flower quite satisfactorily under a deciduous tree such as a peach or apricot. These trees will provide plenty of light in the Winter and moderate shade in the Summer. However for the more serious grower with a number of plants I suggest that you invest in a shade house which will give much better control over our growing conditions. Orchids are best grown raised up from the ground on benches of inverted pots, this provides air movement around the plants and isolates them to a certain degree from attack by snails and slugs.
TYPE OF GROWING MEDIUM ORCHIDS REQUIRE IN CULTIVATION.
The medium (sometimes referred to as compost)that Epiphyte grow in under cultivation conditions must drain freely. This means no free water should remain in the medium. Therefore potting soil or garden soil must not be used. The roots of Epiphyte require air around them at all times as they do in nature. The medium used by the majority of growers consists of composted pine bark pieces, obtainable from most Garden Centres or Nurseries as Orchid bark. This provides for air space between the bark pieces within the pot which, if watered regularly, remains damp but not wet. This will then provide just the conditions required for the orchid to grow. Other materials such as marble chips, polystyrene granules, perlite etc. can be added to the bark mixture. Terrestrials require quite different treatment, they can be grown in a good quality potting soil with the addition of a small quantity of blood and bone but at no time apply non-organic fertilisers as they are quite intolerant to potash and phosphorus, applications of which will lead to the death of the orchid.
I would suggest adding a 'quality" soil wetting agent at the beginning of summer and at the commencing of autumn to ensure an even and uniform penetration of water.
HERE ARE A FEW SIMPLE HELPS TO GET STARTED
Cymbidium Orchids should be bought under some form of opaque covering when the flower buds appear - fibreglass, polyscrim or ant such to allow maximum light to the plants.
Cymbidiums require plentiful watering during summer and less during the winter. Cymbidiums are what we call 'heavy feeders' - that means fertilise at least once a fortnight. For vigorous plants once a week would be ok. Any of the propriety brands of fertiliser are suitable. Once a month thoroughly flush the pots with fresh clean water to remove a build up of salts.
Cymbidiums come in many colours and sizes. The best way to choose is to go along to a nursery or one of the many orchid shows during Spring when the majority bloom.
Can I plant them in the garden? Is a question a lot of people ask. It is possible if lots of preparations are made, but for all intents and purposes it is not really practical. Cymbidiums require air around their roots at all times and will quickly die if planted in the soil.
The medium that is used in pot culture is referred to as compost and consists of such materials as pine bark chips, polystyrene chips, peatmoss, in fact any material that drains freely yet remains damp for some time.
For the beginner the best advice is to purchase prepared orchid mix compost available from most general Garden Centres or Nurseries.
Most people start with a Cymbidium then feel they would like to grow some other orchid. The choice is huge, but for a beginner I would suggest some of the Australian Native Dendrobiums. These grow just as easily as Cymbidiums and require much the same treatment. The main difference is that they do not need as a lot of fertiliser. During the spring, summer and autumn, once a month at half the recommended strength is sufficient. None is required during the winter months. These flowers are quite different to Cymbidiums, being generally smaller, starry shaped, profuse and often highly perfumed. They flower mainly in the spring but some of the newer hybrids, which are readily available, will flower on and off throughout the year.
Another genus easily grown is the member of the Cattleya family. These are the so called 'Chocolate Box' orchids - the type that used to be depicted on boxes of chocolates and were associated with romance and young love. There are many different forms of Cattleya ranging from those with huge flowers up to 6 inches across to tiny ones with flowers one to two inches across but make up for the lack of size with numbers of flowers, anything between 4 - 20 flowers per spike.
Cattleyas come in all colours except black, and if you want to use your imagination there are even blue ones.
All aforementioned orchids will grow in Adelaide throughout the year without artificial heating, only requiring shade from the more severe hot weather of around 50% and some protection for the developing flowers. The Cymbidiums and Australian Natives prefer to grow on benches whilst Cattleyas like to be up high in the shade house.
WHERE CAN YOU LEARN ABOUT ORCHIDS?
There are several orchid clubs within the Adelaide metropolitan area and country districts of S.A. that cater for new growers.
I would suggest this is a good place to start. Details can be obtained from the secretary listed under 'Orchid Club' in the telephone book, garden clubs listed on our fact sheet section or by attending one of the many Orchid Shows put on each year at various venues.
All your Orchid repotting and dividing should have been completed by now. With the hot weather starting it is still important to keep a close watch on the plants. When the weather is cool and the atmosphere is moist, the Orchids should only need to be watered twice a week (still check the pots each day to make sure the soil has not dried out). Once the temperature reaches about 36 degrees C, I would suggest that you water the plants every day if needed.
During the Summer time water the plants at sundown as well as wetting the leaves. If there is a breeze the leaves will cool down as the water evaporates. Cooling down helps to initiate new flower spikes for next year.
Place wood shavings or leaf mulch on the floor where the plants are. Excess water that drains through the pots will be absorbed by the sawdust or mulch and will help to provide humidity around the plants.
Feed the plants this time of year with a low nitrogen fertiliser (Bloom Booster) to assist the development of next year's flower spikes.
Keep a close eye on the leaves to make sure the plants are not attacked by pests or fungi. If there is a problem, take a specimen in a sealed plastic bag to your nearest Nursery or Garden Centre for identification.
Now is the time to fertilize with a low Nitrogen and higher Phosphorus and Potassium level. This will help the new flower spikes to develop for next flowering season.
This is normally the hottest and driest month of the year, so it is important to keep the humidity in the Orchid House. Make sure that the hot, dry winds are prevented from getting in and drying the plants out.
The best height to have your bench is about 30cm off the ground. Have a good depth of ground mulch spread underneath the benches. This will collect the moisture that drains through the bottom of the pots and this in turn will help to raise the humidity.
Materials such as wood chips, pine bark, wood shavings and seaweeds are all good moisture collectors. Watering in the late afternoon is beneficial especially when there is a breeze as this will cool the plants down after a hot day. If the weather is cool, you may only need to water every two to three days. If it is hot then watering may be needed every day.
Most important, keep the snail bait around the plants when the flower spikes appear to prevent damage to the buds.
The correct time to divide up or pot Orchid plants is after flowering. Non flowering bulbs can be potted from September to October, depending on the season. Make sure that all cutting tools are sterilised in a domestic bleach before you begin to cut up the plants.
Before potting check that the Orchid Potting mixture is moist but not too wet. Tap the plant out of the pot and shake the old growing media away from the roots. Now cut and trim off any dead and broken roots. To avoid over potting choose the correct size of the container which your plant will be planted in comfortably.
When you divide Orchids, it is important to select the correct area to cut to minimise damage to the bulbs. As you cut through the Orchid plant make sure to include at least one back bulbs with two young healthy bulbs (note that young bulbs take two or three years to flower). The back bulb is the bulb with no leaf.
Fill approximately one third of the new pot with Orchid potting mix and then place your plant into the pot. Make sure that the top of the pot is approximately level with the bottom third of your orchid bulb and than add the rest of the potting medium into the container.
Give the plant a good drink until the water flows out of the drainage holes in the bottom of the pot. The Orchid plants like to be kept moist all the year round but not wet. To answer the age-old question, I cannot tell you how often to water the plants, but only suggest that common sense is the only way. Weather conditions and soil mixtures both control how often you water the Orchid plants. One thing is that the plants love having their leaves watered as well as do their roots, but do not over water.
Keep the pot plants spaced apart. Otherwise, the flowering spikes will be reduced next year. The most important point to remember is keep the plants free from insect pests.
Fertilising the Orchids should be started in the peak growing season to obtain the best growth structure. They can be fed with a slow release or half the strength of the general recommended dose of liquid fertilisers.
Most important: - prior to feeding liquid fertilisers, make sure you flush the potting medium in the Orchid container with clean water to eliminate any salts built up from previous fertiliser applications.
I would suggest adding a quality soil wetting agent at the beginning of summer to ensure an even and uniform penetration of water.