Sunday, September 28, 2008

Orchids


One of the great things about gardening is the wide variety of forms it takes. There are types of gardening that suit almost all temperaments, and most of us can find one that suits. For some it is the extensive cultivation of vegetables that is most satisfying, while others want to create an elaborate landscape. Still others are focused on making a peaceful place for their relaxation, while others want flowers, sometimes at the expense of all else. There are even some who prefer to grow challenging plants, so they can have the thrill of raising flowers that others cannot succeed with.
Sometimes these groups overlap, and surely those who are looking for plants that promise exciting and superb flowers, yet can also offer a degree of difficulty in cultivation, are drawn to try the many members of the orchid family. They are sometimes drawn in by those that are easy to cultivate - the Cymbidiums or Australian Dendorobiums – and then find themselves moving on to more and more challenging plants.
Among the orchids there are plants that are about as challenging as it is possible to find in the gardening world, but there are also plenty that are relatively easy to grow and certainly offer a great return in flowering display.
There are over 20,000 species of orchid in the wild and almost innumerable hybrids. They grow almost everywhere in the world – the only continent without orchids is Antarctica. There are wonderfully delicate native orchids, usually without large flowers, but often deliciously scented, and well worth looking out for in the forest. Some of these are amenable to cultivation and make charming plants for the bush house or cool conservatory. At the other end of the scale are the warm temperature beauties with chocolate box flowers.
Most cultivate orchids are epiphytes, or lithophytes – they live on trees or on rocks – so they obviously have need perfect drainage. Most will grow well on a potting mix made of pine bark, readily available from nurseries. Do not plant in ordinary soil or common potting mix- your plant will not thrive at all.
As many cultivated orchids are derived from plants that live in tree canopies, some sort of cover from harsh sunlight is essential. A shaded conservatory will serve well, or a specially constructed shade house. Do not forget that plants grow at all levels in the forest and plants that grow higher in the canopy will need more light than those whose natural habitat is the forest floor. As a general rule, if the leaves look lush and drawn, they are probably not getting enough light, while, on the other hand, if they are yellowish and unthrifty, they are probably getting too much light.
Good air circulation is also important, as you would expect from plants that live in forest canopies. If orchids are grown in glasshouse or conservatories, where they can be supplied with extra warmth over winter, it is important to maintain good air circulation by using fans.
Watering and feeding can be a bit of a challenge to the beginner, but it is best to remember that, in the wild, these plants receive a steady flow of nutriment from their environment, and they never sit in a pool of water. For the home cultivator, that means ensuring the plants have a stream of food in the growing season – spring, through to autumn – usually in the form of a slow release fertiliser in the bark, coupled with liquid food in their water. Cymbidiums, which are probably the most commonly grown orchid, are enthusiastic feeders and need a constant supply of food.