Living Green – Growing Orchids in the Tropics

Man has been fascinated by beauty, complexity and diversity of flowers from the orchid family (Orchidaceaeare) for thousands of years. The Terrestrial orchid Cymbidium was in cultivation in China over 2500 years ago.

The ancient Greeks used the tubers from Orchis for medicinal purposes.  The orchid is the largest family of flowering plants on earth, comprising over thirty thousand species with over two hundred thousand hybrids in cultivation. Their geographic range covers the planet, from the warm moist tropics to the extremely cold and dry tundra regions. With such a wide range, it is not difficult to find an orchid which will grow in the climatic conditions found in the Virgin Islands, as most cultivated orchids are tropical in their natural habitat.

Orchids may be terrestrial (growing in the earth) or epiphytic in nature (growing on trees, rocks or leaf litter). The inflorescence may range in size from as small as 4 mm to almost ten feet. The orchid seed is a tiny embryo with no food source and therefore for germination to occur in the wild it requires the mycorrhiza fungus to provide a food source. However because of continuous research, these tiny embryos are now germinated in artificial media, allowing dedicated hybridizers to generate many new hybrids which are made available to avid growers and collectors.

In their natural habitat, the thick white roots of the epiphytic orchids attach themselves to the bark of trees or the surface of other plants where they can easily absorb moisture and dissolved nutrients. They are usually found growing high up in forest trees and are accustomed to plenty of light and air circulation and usually require a maximum of twelve hours of sunlight.  If you can recreate these conditions within your home or in your garden you can grow these beautiful plants easily.

Here are some guidelines for recreating the conditions discussed above:

The ideal medium for growing orchids in pots comprises an equal amount of bark, organic matter, sphagnum moss, coconut fibers, and perlite. This mixture ensures adequate air circulation for the plants.

Before planting your orchids in your chosen location observe the movement of the sun during the day, as orchids grow much better receiving maximum sunlight from the morning to midday sun and being in shade from the hotter afternoon sun.

Check your pots regularly for dryness and water when the first 2 inches of soil have dried out.

Orchids should befertilized twice a month during its blooming season with a balanced fertilizer. Many excellent blends exist for use by the orchid grower. Please read and follow the directions carefully.

When your orchid is finished its first blooming season, cutting the stalk at least 1 inch above the plant's base with a sharp knife ensures an equally beautiful bloom the second time around.

The neophyte, who is intrigued by these flowers, would want to begin with species that are easily available and replaceable by local suppliers. Here are four tropical varieties which are easy to grow and would provide years of satisfaction once you provide the right conditions for their growth:

The Cattleya orchid requires bright light with temperatures between 55 to 90 degrees Fahrenheit, up to 80 percent humidity and alternating wet and dry conditions. It may be planted in coarse tree bark. Coconut fibers will work as well.

The Phalaenopsis, the moth orchid and thePaphiopedilum also require bright light with temperatures between 65 to 85 degrees Fahrenheit and humidity up to 70 percent humidity. These plants should not be allowed to dry out and would welcome being planted in medium bark or a fluffy moss mixture.

The Vandaceous Orchid is not very different from the Phalaenopsis orchid, although they have special cultural requirements.  Vandas are epiphytic and originated in the warm islands of the South Pacific and prefer exposure to full sunlight, warm temperatures and high humidity. These orchids are grown successfully in many climatic regions but thrive and flower best in the tropics, their native habitat.

When purchasing plants for the first time, look for plants that are in full bloom with unopened buds. You will experience the pleasure of newly opened flowers, and would know what to expect when your plants bloom for the second time.

You can find much more information on growing orchids in the tropics on the internet. Enjoy growing plants in the tropics. Our next article will focus on using organic fertilizers to grow healthy and disease free plants.

Esther Georges is the Deputy Director of the National Parks Trust of the Virgin Islands.