Orchids have been used in traditional medicine in an effort to treat many diseases and ailments. They have been used as a source of herbal remedies in China since 2800 BC. Gastrodia elata is one of the three orchids listed in the earliest known Chinese Materia Medica (Shennon bencaojing) (c. 100 AD). Theophrastus mentions orchids in his Enquiry into Plants (372–286 BC).
Many neotropical orchids are pollinated by male orchid bees, which visit the flowers to gather volatile chemicals they require to synthesize pheromonal attractants. Males of such species as Euglossa imperialis or Eulaema meriana have been observed to leave their territories periodically to forage for aromatic compounds, such as cineole, to synthesize pheromone for attracting and mating with females. Each type of orchid places the pollinia on a different body part of a different species of bee, so as to enforce proper cross-pollination.
Epiphytic orchids, those that grow upon a support, have modified aerial roots that can sometimes be a few meters long. In the older parts of the roots, a modified spongy epidermis, called a velamen, has the function of absorbing humidity. It is made of dead cells and can have a silvery-grey, white or brown appearance. In some orchids, the velamen includes spongy and fibrous bodies near the passage cells, called tilosomes.
The main characteristic of this type of orchid is its very pleasant aroma, which means you will likely smell it even before you see it. The pure white flowers release their scent at night, are frequent bloomers, and can bloom all year long in many places. They are a small but showy type of orchid, and their leaves are long, reed-like in shape, and light green in color. They are also easy to grow and are low-maintenance flowers.
The second type, the nobile Dendrobium, grow warm in the summer but require a cool winter period to induce flowering. They need to experience temperatures in the 40s to low 50s (preferably) in order to flower well. They are distinguished by bearing fuzzy, flat, round, colorful flowers close to stem, which cover most of the stem on a well-flowered plant.
Grammatophyllum speciosum is the largest type of orchid and grows up to three meters in height. The world’s most expensive orchid, Shenzhen Nongke, sold for $200,000 at an auction in 2005 and is named after the university that developed it for eight years. Sri Lanka’s Kadupul flower, on the other hand, is considered the most priceless because it blooms just once a year in the night and withers before dawn breaks.
The variety of orchid plant types is amazing. Some bloom for weeks at a time, while others keep their flowers an amazing four months or more. Always check the tag that comes with the plant to determine the optimum temperature for your orchid. Choose one that fits in with your normal indoor environment, rather than trying to change your environment to fit the orchid.
A very showy flower, this type of orchid comes in colors that include white, yellow, brown, purple, red, and a few varieties that are multicolored. They can be a challenge to grow, but they grow well if the temperature is below 80 degrees Fahrenheit because they are used to cool or cold climates. The Odontoglossum orchid has stems that can grow up to four feet high and blossoms that can reach up to six inches in width. Between 20 to 150 blossoms grow on each stem, and their petals are ruffled and very fragrant.
The Lycaste orchid genus, similarly to its relative Anguloa, likes intermediate-to-bright light, intermediate-to-cool temperatures, and high humidity. The flowers look rather different, though; they are more-or-less triangular in shape because the sepals point outward while the petals point forward. These orchids are very fun to grow, and will thrive if you get their care right.
Most orchids are not heavy feeders. Many orchids bloom year after year with no fertilizer at all. During active growth, when new leaves are being produced, you may fertilize every other time you water at half the strength recommended on the fertilizer package. However, it's important to deliver water without fertilizer at least once a month to flush excess fertilizer salts from the bark mix and avoid fertilizer burn to the roots.