Orchid Care Information
GOOD LIGHT vs. BAD LIGHT
Light is a key factor in growing healthy orchids. Direct sunlight may cause plants to burn, and too little light will prevent plants from flowering. An ideal location is behind curtains or window blinds. If you receive your plant by mail, expose it to light gradually in stages over a period of several weeks.
Leaf color is a good indicator of the amount of light a plant is receiving. Orchids should have bright green, healthy leaves. Dark green leaves indicate that a plant is getting insufficient light, and yellowish-green or red leaves indicate that a plant is getting too much light. If you suspect a plant is exposed to too much light, feel the leaves. If they feel noticeably warmer than the surrounding air, move the plant to a location with less intense brightness.
Low light, Warm growing orchids enjoy a north or an east, protected west or shaded south windows of the home. Standard household temperatures are adequate. Orchids that are classified as low light, warm growing are: Paphiopedilum or Lady Slipper, Phalaenopsis and Oncidium.
Moderate to high light, Warm growing orchids. These orchids like a lot of light and warm household temperatures. They thrive in a west or south window. From early May to late September, you should watch light levels in south windows to avoid burning; you may have to move your orchid away from the window or place them behind a sheer curtain to decrease light intensity. These orchids like to dry between watering. Orchids that are classified as moderate to high ligh are: Cattleya, Dendrobium, and Vanda.
THE IDEAL TEMPERATURE
To produce beautiful, long-lasting blooms, orchids must produce energy in the form of carbohydrates during the day when the temperature is high and store that energy at night when the temperature drops. This temperature fluctuation is necessary for orchids to bloom. Without a day-night fluctuation of 10-15 degrees Fahrenheit, the plants will grow plenty of healthy foliage but may stubbornly refuse to flower. A night temperature of 60-62 degrees F is ideal for optimum growth, but temperatures as low as 55 degrees F will not harm your plant. Daytime temperatures should range between 70 and 80 degrees F. Temperatures as high as 90-95 degrees F for short periods will cause no harm, however, as long as proper humidity and air circulation are maintained.
THINGS TO CONSIDER: In the world of the orchid, temperature, light and humidity work in conjunction with one another, and unless a harmonious relationship is achieved between them, optimum growth is not possible. In instances of low humidity, high temperatures can be dangerous; in the case of too much atmospheric moisture, the effects of low temperatures can be over-emphasized. A widely held misconception is that all tropical orchids need extremely high temperatures to survive. This is not altogether true, and to subject them to such treatment can be disastrous.
ORCHIDS LOVE HUMIDITY
The ideal daytime humidity for orchids is 50% to 70%. During the summer, when the days are warm and dry, humidity can be increased by placing plants in a shallow dish or tray containing pebbles and water. Be sure to keep the water just below the tops of the pebbles. Never let water touch the bottom of the pot; capillary action will expose the roots to too much water, causing them to deteriorate. To maintain the quality of water in the tray, remove the pebbles every 2 or 3 months and wash them in a weak bleach solution to remove accumulated salts and algae. Do not add bleach or algaecide to water in the tray when it is in use. You can also group your plants together in a single evaporation tray to create a humid microclimate and an attractive display. Just don't place them so close together that air circulation is restricted.
AS A GENERAL RULE: Again, it must be stressed that both temperature and light should be taken into consideration when deciding to increase humidity. Any form of watering, damping down or spraying should not be performed in the late afternoon or evening. The falling temperatures toward the end of the day can cause unnecessary condensation if highly humid conditions are induced; plants will then become covered with a film of water droplets, which can lead to rotting.
AIR MOVEMENT: VENTILATION
In the wild, gentle continual breezes along the leafy canopy of the rain forest are vital for the survival of orchids and other air plants. Air movement acts as preventive medicine for orchids. It helps evaporate stagnant water, trapped during watering, where fungi and bacteria breed. Without ventilation or fresh circulating air, orchids eventually die from rot, lack of a continual carbon dioxide source, or infection. Ventilation also helps orchids tolerate intense light without getting burnt leaves.
You can easily improve air movement in your home so orchids grow happily. During the summer, when temperatures are high, open windows to allow fresh air to come inside. And when wintertime comes, you can use an ordinary oscillating fan to mimic the gentle breezes in the leafy canopy of a tropical forest. It is important to occasionally change the direction of the airflow so the area does not dry out.
WATERING YOUR ORCHID
Always water early in the day so that your orchids dry out by nighttime. The proper frequency of watering will depend on the climatic conditions where you live. In general, water once a week during the winter and twice a week when the weather turns warm and dry. The size of your orchid container also helps determine how often you need to water, regardless of climate conditions. Typically, a 6-inch pot needs water every 7 days and a 4-inch pot needs water every 5 to 6 days.
The type of potting medium being used can also affect your plant's water requirements. Bark has a tendency to dry out more rapidly than sphagnum moss, for instance. It is important to remember, however, that even when the surface of your pot is dry, the root area may remain moist. Poke your finger or a regular wooden pencil an inch into the pot; if it feels moist to the touch or if the pencil looks moist, do not add additional water. The potting medium should always be damp, but not soggy—neither should it be allowed to get extremely dry.
The quality of water used, whether for spraying or watering, is of great importance. Since tap water has often been chemically treated, generally with chlorine, it should be used with caution. The best water for orchids is Reverse Osmosis filtered water, as it has no minerals or chemicals to worry about. This clean water can be controlled easily by the grower.
THINGS TO CONSIDER: The temperature of the water is also important. If the water temperature and the surrounding air temperature are equal, no harm will result, and slight differences either way can be tolerated by healthy plants. Fatal or long-term damage, not easily discernible at first, can result from using water that is too cold.
In their native habitat, orchids scavenge nutrients from whatever happens to be nearby: decomposing leaves, bird or animal droppings, or minerals borne in rainwater. You can help your orchid to grow faster and bloom sooner by feeding it the right fertilizers. Look for products that contain nitrogen (N), phosphorus (P), and potassium (K), along with trace elements such as iron.
Potassium (K) is mainly responsible for the control of flower, and fruit development.Phosphorous (P) for flower production, and Nitrogen (N) for healthy vegetative growth. The amount of feeding depends on the plant concerned, the time of year and general health of the plant. Investigations have shown that feeding should begin with more Nitrogen just when the new shoots are showing, more Phosphorous and Potassium being necessary towards the end of the season.
THINGS TO CONSIDER: Orchids growing in bark need more nitrogen than either phosphorus or potassium. This is because the bark is decayed by bacteria that use a large amount of nitrogen, leaving very little for the plant. Therefore, the most important step to remember when feeding your orchid is to correctly identify the type of fertilizer you should be using. Before feeding your orchid, always read and follow the directions carefully.
REPOTTING YOUR ORCHIDS
Each orchid genus has different requirements for potting media. It is very important to have the correct medium for each type of orchid, depending on whether it is terrestrial or epiphytic—tree dwelling. Growing media commonly include fir bark, coconut husk, sphagnum moss, tree fern fibers and perlite, and frequently a mixture of two or three of these materials. orchids potted in a typical bark medium need to be repotted every 12 to 24 months, depending on the needs of the individual plant.
The primary purpose of repotting is to provide fresh media, not necessarily a larger pot, but pot size should be selected according to the size of the root mass. Orchids like to be a little tight in their pots. Orchids transferred to overly large pots tend to concentrate their energy on root growth and may not show new growth or foliage for several months.
Orchids may be potted in plastic, clay or decorator pots, and the type of pot selected may influence watering frequency; plants in clay pots will need more frequent watering, as they will dry out a little faster. Always select pots with drainage holes; orchid roots in contact with standing water will rot and die, killing the plant. Media in the center of larger pots may remain wet for long periods and become an unhealthy environment for roots. This can be avoided by placing pieces of broken terra cotta in the bottom of the pot. A smaller pot inverted into a larger one can also help with drainage and aeration, with the roots of the plant draped over and around the smaller pot. Some orchids, such as Phalaenopsis, have roots capable of photosynthesis. For these plants, clear pots have become popular, as they allow light to get to the roots.
THINGS TO CONSIDER: Orchids should not be repotted without a compelling reason. If, for example, aeration of the potting materials is poor because of decomposition, it must be replaced. Care must be taken to ensure that new growths and shoots are not overlapping the rim of the pot—large, neglected plants that have been potted for a long time are notoriously difficult to handle, and it is easy to break off new shoots and roots. But, when in doubt, put it off for another year!
- ANNUAL REPOTTING: Dendrobium, Miltonia, Paphiopedilum and Phalaenopsis and their hybrids.
- EVERY OTHER YEAR: Cattleya, Dendrobium, Oncidium, Odontoglossum and their hybrids.
- EVERY THIRD YEAR: Vanda and its allies, Cymbidium
REBLOOMING YOUR ORCHIDS
Each genus of orchid has different requirements for reblooming. Most commercial varieties are very simple to rebloom. Phalaenopsis, Zygopetalum and Odontoglossum require only slight changes in temperature to initiate blooming. Others, such as Oncidium and Dendrobium, bloom on mature new growth and require a change of fertilizer to a phosphorus-rich, blossom-booster formula.Knowledge of watering, temperature and fertilizer requirements for each genus is necessary for successful reblooming year after year.
The pests that usually bother orchids are scale, mealy bug, snails, slugs, and aphids. Your local garden center or nursery can recommend products to you so that you can control these pests. Apply a good fungicide / bactericide monthly as a preventive measure for disease. Check with your local garden center or nursery for recommendations. Viruses can be transmitted by contaminated cutting tools. Clean pots and stakes each time they are used. Wash used pots thoroughly and always keep hands clean when handling your plants as virus can be spread this way. It is advantageous to destroy all plants with virus since they can be a source of infection to your entire collection.
CATTLEYA (cat-LAY-a) - Cattleyas have earned the reputation as the "Queen of Orchids" and are known to the public as the ultimate in floral corsages. While some naturally occurring species are offered by growers, the most popular plants are man-made hybrids derived from combining Cattleyas with some of their close relatives to produce a wide range of colors, sizes and forms.
Temperature: The ideal day temperature is 75-85 degrees F., while the ideal night temperature is 60-65 degrees F. Occasional temperature extremes are tolerated if exposure is not prolonged.
Light: Cattleyas and their relatives require a good amount of light. They enjoy full sun in the morning, but will require shading from about 11am-3pm; less shading will be necessary in the late afternoon. Their leaves should be a light green color, and a darker green color indicates too little sun.
Water: Basically, cattleyas grow best when their potting medium becomes dry in between waterings. These plants are epiphytes in nature, (i.e. growing on top of trees) and are used to drying out between the rains of their natural habitat.
Repot: Cattleyas should not be repotted unless the plant have outgrown the pot (every 2 or 3 years) or when the potting medium begins to deteriorate. Or when the mixture become sour, does not drain rapidly and is invaded by snow mold or shows green mold on the surface. A coarse medium such as medium-grade Fir-bark, or coarse-grade Fir-bark will work well.
Feeding: High-nitrogen fertilizers can be used year round. Feed "Weekly Weakly" (at 1/4 strength once a week)..
Cutting Dead Flower Spike: When the last flower drops, cut your flower spike all the way down the stem. Continue caring for it and wait for a possible rebloom.
CYMBIDIUM (sim-BID-ee-um) - The popularity of miniature Cymbidium is now spreading from Asia to the worldwide orchid community. These ancient flowers have been treasured, in numerous societies, for nearly two thousand years. Many orchid lovers are most charmed by its fragrance and form rather than its petite size.
Temperature: Cymbidium will tolerate considerable summer heat as long as they get cool, mild night temperatures (between 50-65 degrees F.). Cold weather, even down to 28 degrees F. for a few hours each night, will not damage an acclimatized plant, but once the plant spikes or flowers, it should be protected from temperatures below 35 degrees F. Regardless, plants should always be kept free of frost.
Light: Your Cymbidium enjoys the morning and afternoon sun most, yet should be protected from the hot mid-day sun. A light green leaf with just a hint of yellow indicates the maximum amount of sun the plant can take, and a dark green leaf indicates not enough sun.
Water: Watering of Cymbidium is a delicate balancing act. They should not be allowed to go dry, yet they don't care for a soggy environment either. Watering once every seven to ten days is about right. As with everything else, special consideration must be given for the drying effects of varying ambient air temperature and humidity.
Feeding: High nitrogen fertilizers should be used from February until July, while low nitrogen fertilizers should be used from August until January. Feed "Weekly Weakly" (at 1/4 strength once a week).
Repot: Repot every two to three years from February to June with a well-draining medium. Fine bark is suitable in mild summer climates, while a finer medium Orchid Mix works well in warmer summer areas.
DENDROBIUM (den-DROH-bee-um) - Dendrobium orchids are called "Phalaenopsis type" because their flowers resemble those of the Phalaenopsis variety. Phalaenopsis type are evergreen, while other varieties of Dendrobiums shed their leaves in the fall and winter. Dendrobiums are also commonly used as cut flowers because of their sturdy stems and distinctive coloring.
Temperature: The ideal day temperature is 75-85 °F, while the ideal night temperature is 60-65 °F. Occasional temperature extremes are tolerated if exposure is not prolonged.
Light: These dendrobiums enjoy full morning sun, but will require shading between 11am and 3pm - less shading will be needed in late afternoon. An overhead light source is most effective.
Water: Phalaenopsis-type dendrobiums grow best when their potting medium becomes dry between waterings. They are epiphytes in Nature, (i.e. - they grow on trees) and are accustomed to becoming fairly dry between the rains of their natural habitat. Some types may require a time of drought to initiate flowering.
Repot: Repot once every two years in Spring, after blooming, or when new growth starts. A mix of 10 parts fine-grade Fir-bark and 1 part orchid mix will work well in 6" pots and smaller, while medium-grade Fir-bark works well in larger pots.
Feeding: High-nitrogen fertilizers can be used year round. Feed "Weekly Weakly" (at 1/4 strength once a week).
ODONTOGLOSSUM - The Odontoglossum variety of orchids are becoming very popular for ease of growing and long lasting sprays of small, distinct flowers which often have unique color combinations and a pleasant fragrance. They will typically bloom once a year and can be grown in the home, as well as in a sheltered area in the garden. Odontoglossum have been combined with Oncidiums and other related orchid types through hybridizing to offer a seeming endless array of striking color patterns.
Temperature: Most Odontoglossum and their hybrids enjoy intermediate temperature ranges: 75-85 degree F. day & 60-65 degreee F. at night.Light: Most Odontoglossums and their hybrids prefer filtered, subdued light (from 1000 to 1500 ft. candles). The Odontoglossum prefer bright light.The leaves should be bright green as opposed to dark green or reddish green. Reddish green indicates too much light; dark green indicates not enough light.
Water: Odontoglossums should become moderately dry between waterings. Generally, they require more water while the new shoot is growing and less once the bulb has formed. Feed "Weekly Weakly" (at 1/4 strength once a week). Take care to keep water out of the new growth at the base of the plant. Never allow the bottom of the pot to stand in water. Never use artificially softened water.
Humidity: Odontoglossums enjoy moist air, requiring a minimum of 40-50% humidity in the immediate vicinity of the plant. Humidity should be increased with higher temperatures. The ideal humidity is between 55 and 75%, with as much ventilation or air movement as possible without any cold drafts. Humidity can be increased around the plant by placing the pot on an inverted saucer in a baking pan filled with pebbles, rock chips, etc., and water. Keep water level below top of pebbles so that the plant will not have "wet feet" from setting in water.Morning misting of foliage is also helpful, especially during periods of hot weather.
Potting: Repot Odontoglossums at least every two years. As a general rule, repot them when the new shoot is two to three inches tall or when new roots appear. the old mix should be removed from the roots and any dead roots should be removed. If dividing, keep the divisions in clumps of three to five mature bulbs. Medium to fine fir bark is preferred. The base of the new growth should be potted about 1/2" (no deeper) into the fresh bark. Keep mix barely damp until you see the new roots penetrating the bark, then resume normal watering.
ONCIDIUM (on-SEE-dee-um) - The Oncidium orchids are becoming very popular for ease of growing and long lasting sprays of small, distinct flowers which often have unique color combinations and a pleasant fragrance. They will typically bloom once a year and can be grown in the home, as well as in a sheltered area in the garden. Oncidiums have been combined with Odontoglossum and other related orchid types through hybridizing to offer a seeming endless array of striking color patterns.
Temperature: Most Oncidiums and their hybrids enjoy intermediate temperature ranges: 75-85 degree F. day & 60-65 degreee F. at night
Light: Most Oncidium and their hybrids prefer filtered, subdued light (from 1000 to 1500 ft. candles). The Oncidiums prefer bright light.The leaves should be bright green as opposed to dark green or reddish green. Reddish green indicates too much light; dark green indicates not enough light.
Water: Oncidiums should become moderately dry between waterings. Generally, they require more water while the new shoot is growing and less once the bulb has formed. Feed "Weekly Weakly" (at 1/4 strength once a week). Take care to keep water out of the new growth at the base of the plant. Never allow the bottom of the pot to stand in water. Never use artificially softened water.
Humidity: Oncidiums enjoy moist air, requiring a minimum of 40-50% humidity in the immediate vicinity of the plant. Humidity should be increased with higher temperatures. The ideal humidity is between 55 and 75%, with as much ventilation or air movement as possible without any cold drafts. Humidity can be increased around the plant by placing the pot on an inverted saucer in a baking pan filled with pebbles, rock chips, etc., and water. Keep water level below top of pebbles so that the plant will not have "wet feet" from setting in water. Morning misting of foliage is also helpful, especially during periods of hot weather.
Potting: Repot Oncidiums at least every two years. As a general rule, repot them when the new shoot is two to three inches tall or when new roots appear. the old mix should be removed from the roots and any dead roots should be removed. If dividing, keep the divisions in clumps of three to five mature bulbs. Medium to fine fir bark is preferred. The base of the new growth should be potted about 1/2" (no deeper) into the fresh bark. Keep mix barely damp until you see the new roots penetrating the bark, then resume normal watering.
PAPHIOPEDILUM (paff-ee-oh-PED-i-lum) - The Paphiopedilum or Lady's Slipper is by far one of the most unique and intriguing of all orchids. Its exotic, wax-like, richly colored blooms last for weeks and sometimes months. Lady's Slippers have no pseudobulbs but feature attractive, glossy leaves. After leaves are fully formed, the flower stem rises from the center of the new growth to form one of the most unusual flowers in the world. Best of all, they are ideal for home growing.
Temperature: Paphiopedilum are divided into two temperature groups: warm and cool growers. The attractive mottled-leaf types come from the temperate zones and do best with a night temperature not below 60 degrees F. (preferably 65 degrees F.), and a day temperature of 75-85 degrees F. The solid green-leafed types come from the higher, cooler altitudes. They require a night temperature of 50-60 degrees F. and a day temperature of 70-80 degrees F
Water: Paphiopedilum must be kept constantly moist or damp, but not soggy. Check frequently below the surface to determine the need for water. Normal watering intervals are between seven and ten days.
Light: Place in any bright window but protect from mid-day sun. Leaves should be a medium-green color. If they are too pale or yellowish, the plant could be getting too much light. (Approximately the same light intensity as African Violets is preferred.)
Feeding: Good results may be obtained by using a high nitrogen fertilizer year round. Feed "Weekly Weakly" (at 1/4 strength once a week). Paphiopedilum are sensitive to fertilizer burn.
Repot: Paphiopedilum should be repotted every two to three years with a fresh, well draining potting medium, such as fine-grade orchid bark or Orchid Mix. It is important that the base of the growth be potted no deeper than 1/2" in the medium.