The Orchids or orchidaceae family is the largest and most diverse of the flowering plant families, with over 800 described genus and 25,000 species. Some sources show that there are about 30,000 species in this family, but the exact number is unknown since classification differs greatly in the academic world. Each year 800 new species are added. They are found almost everywhere, but the majority of species are found in the tropics and subtropic regions ranging from sea level to almost 5000 meters in nearly all environments, except open water and deserts. More than half of the species are epiphytic Orchids with fleshy tubers and unusual flowers.
Interesting Facts: Orchids, through their interactions with pollinators and their symbiosis with orchid mycorrhizal fungi, are considered by some, along with the grasses, to be examples of the most advanced floral evolution known. All orchid species are protected for the purposes of international commerce as potentially threatened or endangered in their natural habitat, including Cypripediums, Mexipediums, Paphiopedilums, Phragmipediums, and Selenipedium species Orchids. Many other species are protected by both international and national legislation, and while hybrids are supposed to be specifically exempted, hybrid orchids are not allowed into the United States without a CITES (Convention on International Trade in Endangered Species) permit. The reason is that the authorities cannot distinguish the difference between hybrids and species.
Plant Background: Orchids are one of the largest families of flowering plants, challenging other plant families such as the daisy and sunflower. Orchids are a family of monocotyledons. They have a single seedling leaf and their floral parts are in threes. Currently there are known to be 25,000 species of Orchids. Estimates based on the current rate at which new species are being discovered and described, suggest that the number may reach 30,000 in a few years from now. Orchids are a cosmopolitan family found all the way from within the Arctic Circle to Tierra del Fuego (an archipelago at the southern most tip of South America) and the islands south of Australia. The term Orchid is derived from the Greek word orchis, meaning “testicle” due to the appearance of subterranean tuberoids of the genus. The word orchis was first used by Theophrastos during the period 372-371 to 287-286 BC. Theophrastos was a student of Aristotle and is considered the father of botany and ecology.
Flowers: Orchidaceae are well known for many structural variations in their flowers. Some Orchids have single flowers, while others have a raceme with a large number of flowers. The flowering stem can be produced from the base of the tuber (example: cymbidium), from the apex of the main stem (example: cattleya) or from the leaf axil (example: vanda). Orchid flowers are typically zygomorphic (bilaterally symmetrical), while there are some notable exceptions such as Mormodes, Ludisias and Macodes. The Orchid flower, like most flowers has two whorls or coils of sterile elements. The outer whorl has three sepals and there are three petals in the inner whorl. The sepals are very similar to the petals but may be entirely distinct. The upper medial petal is usually modified and enlarged, called the labellum, or lip. In most orchids the inferior ovary is rotated 180 degrees so that the labellum goes on the lower part of the flower, thus becoming suitable to form a platform for pollinators.
Care: Orchids have widely varying habits and can easily accommodate to the type of environment in which they exist. They may be terrestrial, epiphytic or saprophytic. The secret of successful cultivation of Orchids is to provide them with conditions as identical as possible with the environment under which they were growing in the wild. Due to their peculiar nutritional habits, Orchids require special techniques of cultivation if they are to grow healthy and produce a good crop of flowers.
The following factors should be considered as essential care tips to produce healthy and beautiful orchidaceae:
- Light
- Water
- Humidity
- Temperature
- Suitable medium to grow
The optimum in each of these factors varies from species to species and these factors are to be controlled. Orchids are generally grown in special orchid houses, which are of two types –
- Open houses: The open type of house is mainly employed in tropical countries where humidity and temperature are most favorable.
- Closed houses: This sort of house provides some amount of overhead protection from the blazing noon day sun of the tropics, which might cause leaves to burn in some delicate species.
Varieties: Eight percent of all flowering plants are Orchids, making them the largest family of angiosperms. The classification of the family is still problematic because of its size. There are another 100,000+ hybrids and cultivars produced by horticulturists, created since the introduction of tropical species in the 19th century.
There are five recognized sub-families of Orchidaceae:
- Apostasioideae
- Cypripediodeae
- Epidendroideae
- Orchidoideae
- Vanilloideae