Oct 1, 2009

Orchids are for everyone

Not long ago, orchid growing was thought to be the province of the affluent. No longer is this the case. Anyone who wants to can now grow orchids. A great number of people have discovered this reality.

The two major divisions of this enormous flowering family are the terrestrials, or ground growers; and the epiphytes, which have aerial growth habits including aerial roots. Most orchids grown as house plants are in the epiphyte division.

If you go in for orchids, an early item is to learn the flower structure shared by all of them, and the names of the parts. Every flower has three sepals in an outer whorl, and three petals forming an inner whorl. One of the petals, more vivid and showy than the other two, or larger, is known as the labellum or lip. At center is a club shaped structure with the reproductive parts: the anther producing the pollen, and below it the sticky pistil, the female part. The pistil has a stigma and below that the ovary, which after pollination develops into the seed capsule, holding thousands of very tiny seeds.

Next you would learn about the two classes of orchid growth -- sympodial and monopodial. Sympodial describes those producing a number of new stems, which have flowers, leaves and roots, resulting in lateral growth of the plant over time. These have pseudobulbs. Monopodial describes those becoming taller each year with a single upright stem, lacking pseudobulbs but having aerial roots, leaves and flower spikes along the stem.

"Pseudobulb" means the fleshy stem arising from the rhizome or root, made up of thick, overlapping leaves. This structure is important in helping the plant survive poor conditions. In size it may vary from a foot high down to an inch. Each year a new pseudobulb is produced; this will be the source of a flower shoot, which may take several years to appear.

Popular examples of sympodial orchids are Cattleya, Cymbidium, Dendrobium, Paphiopedilum, Phalaenopsis, and Laelia. Examples of monopodials, less frequently grown as specimens, include Vanda, Angraecum, and Aerides.

Requirements of the different species vary quite a lot. As with any plant, your success in growing an orchid is related to giving it the right conditions.

Temperature

Orchids range in temperature requirements from those tolerating coolness to those preferring warmth. You can adjust conditions to a certain extent to satisfy needs of the kind you are growing. For example, in a fluorescent light garden, the upper shelves are warmer than the bottom ones. The closer a plant is to the light source, the warmer it will be.

Humidity

Orchids thrive on high humidity. One method of maintaining high humidity is to place plants over another container filled with dampened sphagnum moss or pebbles. Another way is to mist spray plants early in the morning, keeping water off the flowers. We have grown orchids in our kitchen in a large terrarium. Any sort of clear plastic covering to hold in humidity will be a help, provided it does not result in excessive heat buildup, as may happen in full sunlight. Guard against too much humidity, which can cause diseases.

Air Movement

Circulating air helps keep fungus infections down among orchids. A fan pointed towards the ceiling and operated at low speed is a method we use to keep air moving.

Watering

Orchids do better with underwatering than with overwatering. The potting medium should be dry between waterings. How often to water depends on the medium in the pot, age of plant, humidity, and temperature. In warm weather watering is needed more frequently. Plants in hanging baskets or pots dry out faster than those in standing containers. Plants in bark or fiber require more frequent watering initially than later on, until the medium settles down a little. Osmunda fiber retains water well, so needs watering less often. Small containers dry out faster than large ones. Water orchids growing on slabs by submerging the entire slab in a container of water. Always use water at room temperature.

When blooming begins, water needs rise. When blooming ends, reduce watering to encourage the plant to go into a rest phase. This is not applicable, however, with terrestrial orchids, which continue to grow. Their rest periods come during fall and winter, at which time watering should be cut back by about half.

Light

Most popular orchids do well with about six hours of summer sunlight or its equivalent per day, rising to about ten hours a day in winter or combined sunlight and supplemental light. Epidendrum and Oncidium species respond to high light intensities; Miltonia and Phalaenopsis do better with some shading.

Fluorescent lighting works well with orchids. If it is used to supplement natural daylight, two 40-watt fluorescent tubes are usually enough. If used as the total light supply, then use four tubes. The most intense light area is at the center of the tubes.

In operating a fluorescent light unit for orchids, whether it is a home made setup or a manufactured one, remember that the top shelves are the warmest and the lowest are coolest. It is important not to move plants once the flower spike appears, as this can result in crooked stems. Inexpensive timers can be used as we have done for turning lights on and off. If plants receive artificial light only, 12 to 14 hours a day may be needed, depending on the species. Group plants with similar light requirements -- whether short day or long day types -- so that needs of all will be met.

Containers

Orchids will grow in many types of containers. The epiphytic types are often grown in pots merely for convenience, but the roots wander out of the pot, hang over the sides or wrap around the outside. The terrestrial orchids are limited to pot culture.

For growing epiphytic orchids, you can use slabs of cork, hardwood or tree fern rather than pots. We prefer tree fern slabs, almost for sentimental reasons, as our life in Puerto Rico and Honduras accustomed us to that material and it was locally available. Slabs tend to dry out quickly, so use care to maintain high humidity.

Pots -- both clay and plastic -- are widely used. For heavy, large plants the clay pots are better suited as they give stability. For displaying on shelves, plastic pots may be preferable because of the lesser weight. Unglazed clay pots allow excess moisture to evaporate, a valuable trait for orchids.

Baskets of wood, plastic or metal, lined with sheet moss or coconut fiber, are all in use for orchids. For those kinds with large aerial roots, the slat baskets are particularly suited.

Potting Medium

The terrestrial orchids can be grown in soil, but epiphytic types cannot. Epiphytic orchids require a very porous medium to avoid the root rots that rise from too much moisture. For beginners, the simplest way is to use a commercially prepared orchid medium. Garden shops usually offer a number of kinds, including coconut fiber, tree fern in a variety of forms, fir bark, redwood bark, redwood inner bark, peat moss and others. Experience will help you in making a choice.

For terrestrial orchids, including Paphiopedilum and Cymbidium, make up a mix of equal parts perlite, sphagnum moss, osmunda fiber, ground charcoal and coarse peat. Sharp sand can be substituted for perlite. As you gain insight into the needs of particular plants, you may change the proportions accordingly.

Each of the potting substances mentioned has its advantages and disadvantages. Shredded bark is low in nutrients, and dries out quickly. Osmunda fiber, on the other hand, retains moisture well, but is difficult to work with. Some growers combine the two, to overcome their separate shortcomings.

Choosing Orchids

First choices are not easy, when you are faced with the countless number of kinds of orchids now available. I suggest you begin by evaluating your particular growing conditions, light sources and available space, and decide on an appropriate species on which to concentrate. This will narrow things down, and from there perhaps prices will be a guide. These range from modest sums to hundreds of dollars. For beginners the less expensive are the best investments. We have seen reasonably priced, large flowering specimens in supermarkets.

You can buy orchid plants already in bloom, or those which will bloom shortly after you receive them. There are dwarf kinds and larger ones, suited for different space conditions. Some species give flowers in clusters, others just one at a time or only a few. Some bloom twice a year, some once or even less frequently. Some bloom in spring, others in fall, winter or summer. There are new hybrids as well as standard genera.

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