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These colorful orchids brighten the landscape and the greenhouse. By Andy Phillips and Cynthia Hill Reprinted from the September 1998 issue of Orchids -- The magazine of the American Orchid Society With their vivid long-lasting flowers, vigorous growth and forgiving nature, it would be difficult to name an orchid more ideal for the novice grower than a reed-stem Epidendrum. They have sometimes been called the poor man's orchid for several reasons. They were affordable and widely available during times when most orchids could be cultivated only by the wealthy. They are easily propagated, yielding many plants from one stem; and they are tolerant of a wide range of growing conditions including outdoors. They also have the advantage of being relatively free of insects and flowering reliably throughout the year. If you are new to orchid growing, with a reed-stem Epidendrum you can enjoy a riot of colourful orchid blooms all year with minimal care. Epidendrums in Nature The number of species in the genus varies depending on which taxonomist you ask. At one time, the genus Epidendrum included those plants now classified as the genus Encyclia (around 250 species), Oerstedella (40 to 70 species, many in isolated areas and perhaps extinct in the wild), Psychilus (15 species) and Nanodes (30 species), which includes the species Epidendrum porpax and Epidendrum medusae. Current estimates place the number of Epidendrum species at around 900. How to Choose an Epidendrum Choosing a plant with new plantlets attached to the stem brings a bonus. Many Epidendrum develop Keiki?s (Hawaiian term for "babies"), which are new vegetative growths produced on old stems and flower spikes. Once these Keiki's develop their own 2- to 4-inch-long roots, they can easily be detached from the stem and planted individually in pots. Before acquiring any orchid, it is essential that you understand your own growing conditions, and then compare those with the plant's requirements. Carefully consider what temperature range, light level, humidity and water quality you can provide. Determine if the plant will be grown indoors or outside and how much growing space you have available. Know how many times a week you will be able to water. Have your water analysed to determine if it has a high level of dissolved salts and minerals, which are detrimental to the health of some plants. (Salt build-up appears as a crusty white residue on the pot, roots and the leaves.) True reed-stem Epidendrum are tolerant of poor water quality. Some Epidendrum, however, are sensitive to damaging salts and other minerals such as iron, and need rainwater or deionised water to thrive. As a general rule, warmer-growing plants found at lower elevations are more salt-tolerant than high-elevation, cooler-growing species that generally receive pure rainwater in their native habitats. If your local water supply is high in salts, you may want to consider a reverse-osmosis (RO) system or collect rainwater for those plants sensitive to water quality. If you are unsure about your water, you may want to contact you local water department for an analysis. Growing Conditions Fertiliser Light Water Temperature When growing outdoors in raised beds, you can mix many colour forms of the same species, if desired. However, combining several species in one bed or tub often leads to competition and overgrowth of one species to the detriment of others. In subtropical and tropical climates, reed-stem Epidendrum makes handsome container plants for patios and pool areas. Potting, Repotting and Planting Outdoors Pest and Diseases A slug or snail can make a meal or several flower heads in a single night. The new, non-toxic iron-phosphate-based slug and snail bait (available as Sluggo or Escar-Go) appears to be effective slug and kind to humans and other inhabitants of a yard. It is safer and longer lasting than other snail and slug killers, such as metaldehyde, and equally efficient. Ant colonies in the potting mix or nearby will often lead to scale infestations the can be difficult to eradicate. Sprinkle Diazinon around the perimeter of the plant, carefully following the manufacturer's instructions and safety recommendations. In a greenhouse, mealybug can be problematic on new growths and developing flower spikes. Treat the entire plant by drenching the pot and thoroughly spraying the new growths with insecticidal soap or Orthene 75 percent WP, being sure to follow the application schedule recommended by the manufacturer. Reddish, shrivelled foliage indicates poor root health, most likely due to the root fungus Rhizoctonia. Infection can be controlled using Benomyl-related compounds such as Clearys 3336 WP or Ban-Rot, the disease is best prevented in the first place by regular repotting in fresh mix. Foliage that is distorted or streaked in irregular patterns, in checkerboard shades of green becoming black squares with age, could indicate the plant is infected with a pathogen such as Tobacco Mosaic Virus (TMV). Irregular colour and streaking patterns on the sepals or the petals of the flowers could be a sign of Colour-break Virus. If you suspect a plant is infected with virus, I recommend destroying it, or at least isolating it from the rest of your plants. Plant viruses are spread by fingernails, aphids and other sucking insects, as well as by using non-sterilised cutting tools or pots. You can use disposable latex gloves when handling and repotting your plants to minimise the risk of cross-contamination. There is currently no treatment for these plant viruses. How to Encourage Plants to Flower Epidendrums to Grow Epidendrum radicans (Mexico to Panama) possesses a low-lying, freely branching growth habit, producing roots along the length of the stem. Stems range from 4 inches to 2 feet in length, producing upright terminal 6 to 15 inch tall spikes with up to 10 vivid, reddish-orange, 1-inch flowers that are open at any one time. The flowers open in succession over several months, with up to 40 flowers per inflorescence. It does well in full sun to partial shade. This species is tolerant of temperatures down to freezing. Epidendrum ibaguense (Colombia and Venezuela) grows like Epidendrum radicans, but clumps more, with roots emerging on the lower half of the cane. Arching branches up to 18 inches, with flower spikes another 18 inches, end in a dense head of 1-1/4 inch reddish-yellow to purple flowers with a yellow lip. There can be up to 50 flowers on a stem, with 20 open at a time. The species has an especially attractive growth habit and grows quickly, filling containers rapidly. It takes full sun to partial sun in hot climates, and can tolerate temperatures down to freezing, but not below. Epidendrum cinnabarinum (Brazil) is a robust, erect and clumping plant, resembling a large Epidendrum secundum, often reaching up to 4 feet. The 30-inch-tall flower spikes produce dense heads of up to 40 flowers, with as many as 10 open at one time. Flowers are large, up to 2 inches, coloured orange to red to pink with a yellow lip. Ideally, this plant is grown outdoors in full sun in South Florida and Hawaii. Snap back stems to base after flowering. This species is particularly susceptible to root fungus (Rhizoctonia) when stressed by cool temperatures. It is tolerant of only short periods of cold (night temperatures below 55 F). Try Oerstedella Oerstedella pseudowallisii (Panama and Costa Rica) is free-flowering year round. Plants are up to 24 inches tall, flowers appear on short spikes, are well rounded with heavy substance, in shades of pale, creamy yellow with red spotting and a white lip, and last for two to three months. This is a warm to intermediate grower. Oerstedella schweinfurthiana (El Salvador) is an aggressive terrestrial, reaching 15 feet. It flowers from midsummer to autumn on spikes with more than 100 rounded flowers that last up to three months. The sepals and petals are suffused with orange-purple inside, purple outside, yellow-tipped sepals, lavender lip. Easy to grow, it thrives in full sun. This species is frost hardy to a least 28 F. More Epidendrum for the Beginner Epidendrum raniferum (Mexico to Central America) and Epidendrum pfavii (Costa Rica and Panama) are two species that produce upright canes to 4 feet, with pendulous heads of flowers that emerge on the same canes year after year (so do not cut them). Epidendrum raniferum's 2-inch flowers are light green, finely spotted red with a white, four-lobed lip, and last all summer. Epidendrum pfavii sports 1 1/2-inch hot-pink flowers. Epidendrum pseudepidendrum (Costa Rica and Panama) is free-flowering year round. Its upright canes can reach 5 feet. This warm growing species is not cold tolerant, and is extremely susceptible to leaf-spotting. The astonishing long-lasting flowers have apple-green sepals and petals, and a waxy orange lip that feels like moulded plastic. Do not remove spikes after flowering as they will re-bloom year after year. Epidendrum parkinsonianum (Mexico and Central America) and Epidendrum falcatum (Mexico) have unusual pendent freely-branching growth habits with falcate, succulent leaves up to 20 inches. These plants tolerate both heat and cold, and will grow in bright light to shade. Mount them for best results. Epidendrum parkinsonianum produces up to eight 5-inch star-shaped green flowers with a white, three-lobed lip. Epidendrum falcatum bears 3-inch flowers that are white with a slight blush. Both are fragrant at night and bloom in the late spring. Reed-stem Epidendrum pay many dividends in the garden or greenhouse; they are easy to care for, affordable, widely available, tolerant of diverse growing conditions and are robust growers with many flowers in every colour of the rainbow. Epidendrum can reward the orchid grower with a wealth of brilliant flowers all year long. -o0o- |
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