Varieties of Orchids

Terrestrial Orchids

• Orchids develop in one of two ways: terrestrial orchids grow by means of a root system that is buried in the soil, while epiphytic orchids produce roots that attach themselves to surfaces such as tree bark or rocks. The roots of terrestrial orchids serve the same purpose as do the roots on other plants, absorbing water and nutrients from the soil. Examples of terrestrial orchids include cymbidium, native to the Far East, which can be grown just about anywhere and the Erythodes, a group of orchids whose plants grow from rhizomes with long nodes that produce more new plants.

Epiphytic Orchids

• Epiphytic, or aerial, orchids, produce above-ground roots that depend on the chlorophyll contained in their green tips to absorb the sunlight needed for food production. The cattleya, a native to Central and South America, produces some of most colorful and often fragrant blooms of the entire species and does well in warm climates. Vanda orchids often produce aerial roots that emerge from its stems, which is why this species sometimes is grown in baskets to allow them to spread. Vandas also need frequent watering as they cannot store water.

Climate Classifications

• Different types of orchids require different environmental conditions, reflecting the habitats from which they originate and where they still grow naturally. Both terrestrial and epiphytic orchids are found in all climates that are classifed as cool, intermediate and warm. Exceptions to this rule are the Dendrobrium orchids that grow in all three climates. Paphiopedilum orchids grow in warm climates, producing long-lasting blooms that do best in moderately humid conditions. Also called lady slipper orchids, they produce pouchlike flowers that actually are several of their petals joining together. The vanilla orchid is a leafless vine native to the tropics, whose blooms open in the morning and close later in the day. If not pollinated, the flowers fall off.

Intermediate and Cool-Climate Orchids

• Miltonia and Oncidium orchids do best in intermediate climate zones that range from Ohio west to Nebraska and south to Missouri, and central portions of South America. Also called pansy orchids, Miltonias resemble violas, bearing profusions of fragrant flowers. Oncidium, or dancing-lady orchids, grow naturally from Florida to Argentina, producing flowers that bloom for six weeks or longer. Pleione orchids are native to hilly areas of China and the Himalayas, where they grow near snow-covered borders of forests.

Wild Orchids

• No discussion of orchids is complete without mentioning their wild cousins known as the pink lady slipper, or Cypripedium acaule. Producing pouchlike flowers that are whitish pink to magenta, lady slippers, also called moccasin flowers, grow wild in most areas of the eastern half of the United States and much of Canada. They thrive in coniferous forests in soil that is rich in decaying vegetation. Lady slipper seeds take years to develop into plants and for this reason are considered endangered in areas where they are dug up by gardeners who want to grow them in their gardens. Because lady slippers depend on a type of fungus in the soil for their nutrition, they cannot be transplanted to areas where this fungus does not exist.