With ageing, the pseudobulb sheds its leaves and becomes dormant. At this stage, it is often called a backbulb. Backbulbs still hold nutrition for the plant, but then a pseudobulb usually takes over, exploiting the last reserves accumulated in the backbulb, which eventually dies off, too. A pseudobulb typically lives for about five years. Orchids without noticeable pseudobulbs are also said to have growths, an individual component of a sympodial plant.
Water thoroughly. When you do water, do it like you mean it. Different growers have different rules, but many professional growers turn on their sprinklers for 8 or more minutes. Successful home-growers sometimes dunk their plants, pots and all, into a bucket or sink of water. Some varieties, such as vandas, can be left floating in water for a surprisingly long time. The idea is to make sure the velamen is completely saturated. You want tiny droplets hanging on the roots after watering. This means the plant is completely hydrated.
Epidendrum orchids are among the oldest genera in the orchid taxonomy. Originally, this genus included all epiphytic orchids. As knowledge of the different types of orchids expanded, the classification became much more refined; for example, there are now some terrestrial species in the Epidendrum genus, and a great many other species have been moved to other genera. Still, over 1000 Epidendrum species exist. They are usually easy to grow, and most have tall canelike pseudobulbs that lean all over the place and frequently produce keikis. Fun orchids!
The Orchideae tribe is the largest tribe within the Orchidoideae subfamily, and contains a variety of flower forms. Flowers in this tribe dominate the orchid flora in the temperate Northern Hemisphere, though they can also be found in East Asia. These orchids usually have a three-lobed lip without a basal spur, prominent caudicles, and erect anthers.
Orchids have many associations with symbolic values. For example, the orchid is the City Flower of Shaoxing, China. Cattleya mossiae is the national Venezuelan flower, while Cattleya trianae is the national flower of Colombia. Vanda 'Miss Joaquim' is the national flower of Singapore, Guarianthe skinneri is the national flower of Costa Rica and Rhyncholaelia digbyana is the national flower of Honduras. Prosthechea cochleata is the national flower of Belize, where it is known as the black orchid. Lycaste skinneri has a white variety (alba) that is the national flower of Guatemala, commonly known as Monja Blanca (White Nun). Panama's national flower is the Holy Ghost orchid (Peristeria elata), or 'the flor del Espiritu Santo'. Rhynchostylis retusa is the state flower of the Indian state of Assam where it is known as Kopou Phul.
The orchid plant is also unique in its morphology (form or structure). We can begin with the leaves and work our way down to the roots. The leaves of many orchids in cultivation are unique in that they are specifically designed for water conservation (as is true for almost every orchid structure). They have a heavy waxy leaf coating and specialized stomata (openings through which the leaf “breathes”) that help to prevent water loss during transpiration (the act of the plant “breathing”). Many orchids utilize CAM photosynthesis as well, which in essence means that the plants collect materials during the day and then process them at night.
The structure of the leaves corresponds to the specific habitat of the plant. Species that typically bask in sunlight, or grow on sites which can be occasionally very dry, have thick, leathery leaves and the laminae are covered by a waxy cuticle to retain their necessary water supply. Shade-loving species, on the other hand, have long, thin leaves.
Also called Cockleshell orchids, they have no fragrance, but they do bloom for several consecutive months, making them appealing for people who want color in their garden for long periods of time. The Encyclia orchid has dangling petals and sepals, which is why some people say it resembles an octopus. It thrives when planted on an orchid mount because this simulates the epiphytic growing conditions found in the wild, and it comes in colors such as yellow-white with purple throats at the top.
Some orchids have water-storing organs, and some do not. If you have a type of orchid that has the ability to store water, such as cattleyas or oncidiums, you should allow the orchid to completely dry out before watering. If you have a type of orchid that does not have water-storing organs, such as phalaenopsis or paphiopedilums, you should water the orchid before it is entirely dry.
Here again, the type of potting mixture will be a major factor in determining how often you should water your orchid. You should also pay attention to the condition of the potting mixture, as aged growing medium that has broken down into finer particles will hold more water and take longer to drain than fresh medium, thus requiring less frequent watering.
A majority of orchids are perennial epiphytes, which grow anchored to trees or shrubs in the tropics and subtropics. Species such as Angraecum sororium are lithophytes, growing on rocks or very rocky soil. Other orchids (including the majority of temperate Orchidaceae) are terrestrial and can be found in habitat areas such as grasslands or forest.
The potting mixture, or growing medium, for a phalaenopsis orchid should be good at both absorbing water and providing airflow to the roots of the plant. Therefore, consider using media such as tree bark, coconut coir, clay pellets, perlite, pumice pebbles, and sphagnum moss, either on their own or blended together. If you live in a humid climate, choose a courser potting mixture that dries quickly and provides the best drainage. On the other hand, those who live in a dry climate should use a finer medium that will dry more slowly and hold more moisture.
The Sobralia orchid genus grows ubiquitously in much of South and Central America; I've heard them called "ditchweed"! They have beautiful, short-lived flowers whose appearance is somewhat similar to a large Cattleya orchid. Flowers can be more than 6 inches (15cm) across in some species. The plants can get quite large, however, so you need to have enough space for them!
If your Catasetum orchid leaves begin to yellow and drop off, do not despair; this deciduous orchid loses its leaves naturally during winter dormancy. There is much variation in appearance between Catasetum species, but one feature they all have in common is the trait of producing male or female flowers, which bear little resemblance to each other. The male flowers have an anatomical trigger that forcefully ejects pollen onto visiting bees.
Cymbidium carry tall stems with many flowers that have a more typical orchid shape. They are easily identified by their grassy leaves, and they readily form large clumps. Most common are the cool-flowering types, which need to experience a cooler winter (nights in the 40s for some time in the fall) in order to initiate flowering. Once the flowers open, they can last for up to two months or more, especially in a cool environment. These are very showy and rewarding plants, and a plant in a six-inch pot can carry three stems with 15 or more flowers each, depending on the type.