General Orchid Care, part 2

Orchid 102 – General Orchid Care

Last month, we identified the five most popular orchids today – Cattleya, Dendrobium, Oncidium, Paphiopedilum, and Phalaenopsis. All are extremely easy to care for while they are blooming. Watering once or twice a week thoroughly and providing a well lit space is usually sufficient. It also helps to have comfortable humidity and gentle air movement. Anything more is asking for trouble – such as misting the flowers, polishing the leaves, repotting the plant, or “babying” the orchid in any way! The quickest way to kill a perfectly good orchid is by loving it too much.

Panic can set in when the initial flowers fade, leaving a barren pot with not so attractive leaves. Some owners don’t realize that orchids bloom annually and throw the helpless plants away as if they were holiday Poinsettias. Others recognize the value of the tropical epiphytes but imagine the ‘rainforest-like’ care is beyond their capability.

For those lucky enough to live in cities where ‘Orchid Boarding’ is offered, there exists an easy re-blooming option in which out-of-bloom plants are shipped off to participating greenhouses for professional care. Typically costing pennies a day, this service is wildly popular with area residents who can gradually acquire sizeable orchid collections without having to worry about space considerations. ‘Summer Camp’, as some call it, is easy fodder for cocktail party conversation, for it is often greeted with disbelief by newcomers who cannot believe such a program could exist.

Hats go off to those budding horticulturalists who wish to take this delightful hobby to the next level – the joy of re-blooming an orchid at home. Mastery of the following guidelines will ensure success.

Basic Orchid Culture

Every attempt should be made to duplicate their native conditions. Although not entirely practical, old growth mahogany trees covered top to bottom with bromeliads and ferns would be a nice addition to any living room. Throw in a few howler monkeys, toucans, and leaf-cutter ant colonies along with some low lying morning fog and most orchids will feel right at home.

Air Circulation – In the wild, constant breezes help with photosynthesis and control disease. Slow turning over-head or table fans should run 24 hours a day.

Fertilizer – Use sparingly for orchid roots are sensitive! Weak solutions of a general purpose plant food applied several times a month are usually sufficient.

Humidity – Insufficient levels are often the reason for unopened flowers falling off (aka bud drop). Strive for at least 50% year round which requires a gauge to measure it and the possible addition of evaporative water pans (aka humidity trays) or, for larger collections, a small humidifier.

Light – Two distinct intensities are needed for the aforementioned five popular orchid genera. Cattleyas, Dendrobiums, and Oncidiums prefer filtered direct light which is defined as full sun that is diffused by sheer curtains, partially turned blinds, or outside under a trellis. Paphiopedilums and Phalaenopsis like indirect light which is nothing more than shade or early morning/ late day sun.

Potting Media – Somewhat varied by geography (Ex. Hawaii often uses lava rock) and lifestyle (Ex. Wine drinkers like bottle corks). Local commercial growers work with cypress mulch for Cattleyas and Oncidiums, fir bark for Dendrobiums, a blend of coconut husk, charcoal, and expanded rock for Paphiopedilums, and either peat moss or sphagnum moss for Phalaenopsis. Clay pots are usually preferred over plastic except for Lady Slippers which are particularly sensitive to drying out.

Temperature – All the popular types are comfortable between 60 and 90 deg F. The lone exception occurs for a few weeks in the autumn when Moth orchids are chilled nightly to 50 deg F in order to instigate a flower spike. Exposing a tropical plant to cold causes foliar stress – yellow leaves, stunted new growths, etc. Extreme heat can be tolerated if the roots are well watered.

Watering – Thoroughly drench once or twice a week directly from the tap. Well, rain, or purified water is preferred by not necessary. No ice cubes!

Once the hobbyist acquires 20 orchids or so, it may be time to consider bonding with other like-minded individuals. The internet is loaded with orchid chat rooms and great web sites but there is nothing better than seeing the plants personally. Major cities have orchid societies which meet monthly to show off their specimens ( and area botanical gardens and conservatories boast outstanding collections (

Monday, June 1, 2009 - 17:45