Orchid Information
phalaenopsis
Phalaenopsis, the moth orchid, is perhaps the best orchid for growing in the home, and is also a favorite with greenhouse growers. Well-grown plants can flower often, sometimes with a few flowers throughout the year, though the main season is late winter into spring. Average home temperatures and conditions are usually sufficient. Flower stems on certain hybrids can be forced to rebloom by cutting the tip off after the initial flowering. Only healthy plants should be induced to flower repeatedly. Culture for Doritis, a related genus, thought by some to be con specific with Phalaenopsis, and Doritaenopsis, a hybrid between the two genera, is the same as for pure Phalaenopsis.
light
Light is easy to provide for phlaenopsis. They grow easily in a bright window, with little or no sun. An east window is ideal in the home; shaded south or west windows are acceptable. In overcast, northern winter climates, a full south exposure may be needed. Artificial lighting can easily be provided. Four fluorescent tubes in one fixture supplemented by incandescent bulbs are placed 6 to 12 inches above the leaves, 12 to 16 hours a day, following natural day length. In a greenhouse, shade must be given; 70 to 85 percent shade, or between 1,000 and 1,500 foot-candles, is recommended. No shadow should be seen if you hold your hand one foot above a plant's leaves.
temperatures
Temperatures for phalaenopsis should usually be above 60 F at night, and range between 75 and 85 F or more during the day. Although higher temperatures force faster vegetative growth, higher humidity and air movement must accompany higher temperatures, the recommended maximum being 90 to 95 F. Night temperatures to 55 F are desirable for several weeks in the autumn to initiate flower spikes. Fluctuating temperatures can cause buddrop on plants with buds ready to open.
water
Water is especially critical for phalaenopsis. Because they have no major water-storage organs other than their leaves, they must never completely dryout. Plants should be thoroughly watered and not watered again until nearly dry. In the heat of summer in a dry climate, this may be every other day; in the winter in a cool northern greenhouse, it may be every 10 days. Water only in the morning, so that the leaves dry by nightfall, to prevent rot.
humidity
Humidity is important to phalaenopsis, the recommended humidity being between 50 and 80 percent. In humid climates, as in greenhouses, it is imperative that the humid air is moving. Leaves should be dry as soon as possible, always by nightfall. In the home, set the plants on trays of gravel, partially filled with water, so that the pots never sit in water.
fertilize
Fertilize on a regular schedule, especially if the weather is warm, when the plants are most often growing. Twice-a- month applications of high-nitrogen fertilizer (such as 30-10-10) are appropriate where bark-based media are used. Otherwise, a balanced fertilizer is best. When flowering is desired, a high-phosphorus fertilizer (such as 10-30-20) can be applied to promote blooming. Some growers apply fertilizer at one-quarter strength with every watering; this is best for warm, humid conditions. When cooler, or under overcast conditions, fertilizer should be applied twice per month at weak strength.
potting
Potting is best done in the spring, immediately after flowering. Phalaenopsis plants must be potted in a porous mix. Potting is usually done everyone to three years. Mature plants can grow in the same container until the potting medium starts to decompose, usually in two years. Root rot occurs if plants are left in a soggy medum. Seedlings usually grow fast enough to need repotting yearly, and should be repotted in a fine-grade medium. Mature plants are potted in a medium-grade mix. To repot, remove all the old medium from the roots, trim soft, rotted roots, and spread the remaining roots over a handful of medium in the bottom of a new pot. Fill the rest of the pot with medium, working it among the roots, so that the junction of the roots and the stem is at the top of the medium.
the american orchid society
The American Orchid Society invites you to join us and learn about the world's most fascinating flowers and plants. Your membership entitles you to our monthly magazine Orchids, a free copy of the AOS Orchid Source Directory, a 50 percent discount coupon good toward the purchase of one of our cultural publications, a 10 percent discount on items purchased through our Web site's electronic store and reciprocal benefits at more than 200 botanical gardens and arboreta associate with the American Horticultural Society through its Reciprocal Admissions Program. All this and much more can be yours as a member of the AOS.
American Orchid Society
16700 AOS Lane
Delray Beach, FL 33446-4351
Tel 561-404-2000 Fax 561-404-2100
E-mail TheAOS@aos.org
Orchid Information
cymbidium
These orchids are prized for their long-lasting sprays of flowers, used especially as cut flowers or for corsages in the spring. There are two main types of cymbidiums standards and miniatures. Where summer nights are warm (above 70 F), only miniatures can be recommended, because many are more tolerant of heat and able to flower in warmer weather.
light
Light is important for growing cymbidiums. Coming from cool and bright areas in Asia, they need high light but cool temperatures. In many southern climates, high summer temperatures, especially at night, may prevent the plants from blooming. The maximum amount of light possible, short of burning, should be given to the plants. This means only light shade during the middle of the day, or about 20 percent shade. In cool areas (such as coastal California), full sun is tolerated. Leaves should be a medium to golden green in color, not dark green.
temperatures
Temperatures are another critical factor in flowering standard and miniature cymbidiums. During the summer, standard cymbidiums are usually grown outside in semishade, where day temperatures should be 75 to 85 F (or more), but night temperatures in the late summer to autumn (August to October) must be 50 to 60 F to initiate flower spikes. Optimum temperatures in winter are 45 to 55 F at night and 65 to 75 F during the day. When plants are in bud, temperatures must be as constant as possible, between 55 and 75 F. Miniatures can stand temperatures five to 10 degrees higher than standards and still flower. Most cymbidiums can tolerate light frosts and survive, but this is not recommended. Bring them inside when temperatures dip to 40 F. In mild climates, they can be grown outside year round. A bright and cool location inside is best for winter months.
water
Water to provide a constant supply of moisture to cymbidiums, which are semi-terrestrial plants. They generally produce all their vegetative growth during the is spring and summer and need the most water during that period. Water heavily during the growth season, keeping the potting material evenly moist. Reduce water when the pseudobulbs complete growing in late summer. Keep barely moist during the winter.
humidity
Humidity outdoors is usually sufficient during the summer, except in dry climates, where evaporative cooling in a greenhouse is necessary. Keep humidity at 40 to 60 percent during the winter, especially if plants are in bud. Keep the air moving to prevent fungus (Botrytis) from spotting the flowers.
fertilize
Fertilize at the proper time to help cymbidiums flower. During the growth season (spring through late summer), high nitrogen fertilizer (such as 30-10-10) is used. In late summer, use a high-phosphorus, blossom-booster fertilizer (such as 10-30-20), to help form bloom spikes. Fertilize at full strength every week to two weeks. In winter, fertilize once a month.
potting
Potting is usually done in the spring after flowering, usually every two years or when the potting medium decomposes. Shake all of the old potting mix off the roots, dividing the plant if desired. Pick a water-retentive potting mix; medium-grade fir bark with peat moss and perlite is a common mix. Select a pot that will allow for at least two to three years of pseudobulb growth before crowding the pot, while planning on placing the active growing pseudobulb(s) of the division farthest from the side of the pot. Spread the roots over a cone of the mix in the bottom of the pot and fill the container with medium, working it among the roots, tamping firmly. Single backbulbs need not even be placed in mix until new growth and roots are noted. Keep shaded and warm until new growth sprouts, and pot as above.
the american orchid society
The American Orchid Society invites you to join us and learn about the world's most fascinating flowers and plants. Your membership entitles you to our monthly magazine Orchids, a free copy of the AOS Orchid Source Directory, a 50-percent discount coupon good toward the purchase of one of our cultural publications, a 10-percent discount on items purchased through our Web site's electronic store and reciprocal benefits at more than 200 botanical gardens and arboreta associated with the American Horticultural Society through its Reciprocal Admissions Program. All this and much more can be yours as a member of the AOS.
American Orchid Society
16700 AOS Lane
Delray Beach, FL 33446-4351
Tel 561-404-2000 Fax 561-404-2100
E-mail TheAOS@aos.org
Orchid Information
vanda
The Vanda Alliance is made up mostly of warm- and full-sun-growing orchids with colorful flowers. Originating in tropical Asia, they are easily grown in warm climates, where plants are cultivated outside in light shade, such as in a lath house. In climates where winters are cold, they are often summered outside, and grown inside during the winter in a sunny window, or year round in a greenhouse. Smaller growing ascocendas are best outside tropical conditions.
light
Light is a crucial factor in blooming most vandaceous plants. There are three types of vandas: strap-leaved, semi-terete and terete. The first type has broader, flat leaves, while terete types have round, pencil-shaped leaves. The semi-teretes are hybrids between the two, with an intermediate leaf shape. Terete types need full sun, and are best grown in high-light climates. In a greenhouse, give the plants about 25 to 35 percent shade, less in winter if overcast. Leaves should be a medium green, not dark green. In warm, bright climates, you can grow any type of vanda outside (if warm) with partial shade for strapleaved types and semi-teretes (especially in midday in summer) or inside (when cold) in a bright, south window. In climates where winters are overcast, try ascocendas. Grow them outside in summer and in full sun inside during the winter. Be careful to aclimatize plants to avoid burn.
temperatures
Temperatures for most vandas should be warm; a minimum winter night temperature of 55 F is recommended. Colder spells can be tolerated for a short time if it is not windy. Optimum temperatures are 60 to 70 F at night, and a maximum of 95 F during the day. Warmer temperatures mean faster growth, which must be balanced with higher humidity, air movement, and increased water and fertilizer. Days should be warm and humid for optimum plant growth.
water
Water should be applied copiously when the plants are growing, but the roots must dry quickly. Because of this, and their extensive root system, they are mostly grown in slatted-wood baskets, or in pots with a coarse potting medium. If their situation is warm and sunny, they may need daily watering. Water sparingly in the winter or during cloudy weather.
humidity
Humidity of 80 percent is ideal. In tropical climates this may be easy to obtain. In a greenhouse, this is easier to provide by using an evaporative cooler. In the home, place the plants on trays of gravel partially filled with water. Air movement must be strong.
fertilize
Fertilize with a balanced (such as 20-20-20) fertilizer applied full strength once a week during warm weather or use a one-quarter-strength solution at every watering. During cool or cloudy weather, apply fertilizer once every two to four weeks. Use a high-phosphorus fertilizer (such as 10-30-20) every third application to promote flowering.
potting
Potting should be done in the spring. Plants in baskets do not need to be repotted often. Leave them unless the potting medium breaks down. Set the plant, with the old basket intact, into a container of water to make the aerial roots more pliable, and then set plant and basket into a larger basket. For plants in pots, repot in a slightly larger pot, positioning the plant in the center. Use a coarse medium, whether fir bar, tree fern or charcoal, and work it around the roots. Keep shaded, humid, but drier at the roots until new root tips grow. Do not overpot.
the american orchid society
The American Orchid Society invites you to join us and learn about the world's most fascinating flowers and plants. Your membership entitles you to our monthly magazine Orchids, a free copy of the AOS Orchid Source Directory, a 50-percent discount coupon good toward the purchase of one of our cultural publications, a 10-percent discount on items purchased through our Web site's electronic store and reciprocal benefits at more than 200 botanical gardens and arboreta associated with the American Horticultural Society through its Reciprocal Admissions Program. All this and much more can be yours as a member of the AOS.
American Orchid Society
16700 AOS Lane
Delray Beach, FL 33446-4351
Tel 561-404-2000 Fax 561-404-2100
E-mail TheAOS@aos.org