Queen of orchids Cattleya

The queen of orchids, corsage orchid, cattleya or cat orchid is an epiphytic, tropical herbaceous perennial in the orchid family (Orchidaceae). It is native to the American tropics, from Costa Rica to Argentina. The genus name commemorates British horticulturist and orchid enthusiast William Cattley (1788–1835).

Given the right conditions, cattleyas grow readily. They require a special potting medium, which is usually based on coarsely chopped redwood or fir bark. Some growers have success using inorganic, kiln-fired materials. The medium should be allowed to dry completely between waterings. Good air circulation is as important as proper light and humidity. An east- or west-facing window is best. Direct sun will burn the leaves. A leaf with the right amount of sun is mid-green. A dark leaf indicates insufficient sunlight. The temperatures must be between 70 to 85 degrees F during the day and 55 to 60 degrees F at night. The humidity must be above 50%. This can be achieved by placing a baking dish or saucer filled with pebbles under the plant. Add water to the saucer below the surface of the pebbles and set the potted orchid on the surface of the pebbles. Refill the saucer as necessary. Water the plant by placing it in a sink and running lukewarm water through the pot until it flows out the drain holes. Let the pot drain well before returning it to its place. Do not use salt-softened water or water colder than 50 degrees F. Do not use ice cubes. Fertilize regularly after watering with a balanced fertilizer twice a month at half strength or weekly at quarter strength. Repot as needed (usually every two years) in spring or just before new roots sprout from the rhizome. Repotting is needed when the rhizome of the plant protrudes over the edge of the pot or when the potting medium breaks down and drains poorly. The plant can be divided during repotting as long as each division has at least three healthy, plump pseudobulbs. 

The plant has four main parts – roots, the rhizome, the pseudobulbs and the leaves. In nature, the rhizome creeps along a tree limb producing roots and pseudobulbs. In cultivation, the rhizome should be on the surface of the potting medium. Pseudobulbs are swollen stems that grow upright from the rhizome and bear one or two leaves (the Unifoliate and Bifoliate cattleyas, respectively). The pseudobulbs store water (which allows the plant to withstand droughts) but eventually shrivel after their leaves drop. The leaves are thick and leathery. Flowers are produced from the top of the pseudobulb, at the base of the leaf or leaves. A few species produce them from stalks originating at the base of the pseudobulb. Flowers come in many colors. The lip is often of a contrasting color. 

Having been avidly and recklessly collected during the 19th century, cattleyas are now on the CITES Appendix II. Wild-collected plants must be shunned by the consumer, as the collection of the plants from the wild is often done illegally. Fortunately, cattleyas are readily propagated from seed or by tissue culture. They have been hybridized extensively, and most cattleyas in cultivation are hybrids, often involving other closely related genera. Some common intergeneric hybrids are Brassocattleya (= Brassavola × Cattleya), Brassolaeliocattleya (= Brassavola × Laelia × Cattleya), Cattleytonia (= Cattleya × Broughtonia), Cattlianthe = [Cattleya × Guarianthe], Epicattleya (= Cattleya × Epidendrum) and Rhyncholaeliocattleya (= Cattleya × Rhyncholaelia). The genus Sophronitis is now treated as a synonym of Cattleya, so the hybrid Sophrocattleya is now Cattleya and is no longer considered to be intergeneric.

Cattleya orchids are grown as greenhouse plants or houseplants. They can be grown outside in the summer.

Quick ID:

• Thin pseudobulbs that emerge from the rhizome
• Thick, waxy leaves
• Colorful, classic corsage orchid with a prominent lip

Diseases, Insect Pests, and Other Plant Problems:  If kept outside, the plant may be attacked by slugs, snails, thrips, scale insects and mealybugs. Search the plant periodically for spider mites, which are especially problematic if the humidity is too low.

VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti", a plant identification course offered in partnership with Longwood Gardens.