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Scientific Classifications of Orchids

Orchids are widely grown as greenhouse or indoor decorative flowering plants. In the wild, the plants occupy nearly every habitat except the Arctic and glaciated regions. Most orchids grow in moist, tropical and subtropical ecosystems. While orchid flowers vary considerably in shape, color and size, they share a common configuration of three petals and three sepals. The bottom petal is conspicuously shaped with brighter color patterns than the top petals.

Monopodial Orchids
- All orchids are members of the Orchidaceae or orchid family from the order Asparagales. The plants are monocotyledons, with a single shoot at germination. Orchids are divided into two growth-type botanical classifications: monopodial and sympodial. Monopodial orchids produce a central stem that grows continuously from its apical tip, reaching several meters in some species. Flowers and leaves grow alternately from side to side along the length of the stem. Phalaenopsis and vanda are popular monopodial orchids.
Sympodial Ochids
- The second mode of axillary branching in angiosperms is called the sympodial growth habit. Sympodial orchids branch when the growing point on the stem's tip stops its growth due to a terminal flower. The plant subsequently spreads out laterally or sideways to produce new shoots. The adjacent shoots grow to flowering size and stop growing after blooming. The propagation cycle is then repeated. Some widely grown sympodial orchids are cattleyas, laelias and paphiopedilums.
Terrestrial and Epiphytic Orchids
- Another way to classify orchids is by divisions of terrestrial and epiphytic orchids. Epiphytic orchids live high up in trees. Epiphytes adapt to an arboreal environment, shaping themselves to fit around tree branches and developing aerial roots. Epiphytic orchids evolved water-storage organs along the midsection of the stem called pseudobulbs. Terrestrial orchids live on the ground and are rhizomatous, forming underground tuberous corms. The root's shape gives orchids their name, from the Greek word orkhis, meaning testicle.
Taxonomy
- Naming orchids presents a special challenge to the taxonomist. Not only is the orchid family the most numerous with 25,000 to 30,000 wild species, but horticulturists have created hundreds of thousands of orchid hybrids and cultivars. They hybrids may be intergeneric or the result of crossing related species. Each hybrid must be individually named in addition to the genus and species name required by the International Code of Botanical Nomenclature. Most orchids sold on the commercial market are hybrids.

Nature