Paphiopedilum and Phragmipedium Culture Sheets

[Heather]

I'm going to bump these up for newbies. They're really buried here and we never pinned them....I never pinned them...

Paphiopedilum

Paphiopedilum (paff-ee-oh-PED-ih-lum) are the old world tropical lady slipper orchids with species coming from a huge geographic area including India and China through Indonesia and the Philippines to New Guinea. Species are semi-terrestrial, growing in humus and other material on the forest floor or on limestone cliffs, and occasionally on trees. Plants will generally flower from every mature growth, and flowers usually last from one to three months. There are multi-flowered, sequential flowered, and single flowered varieties. They are easy to grow in the home, under lights, or in a greenhouse.

Light
Paphs are good beginner orchids because they can be grown successfully on a windowsill. An east or south facing window is ideal. Paphs also do well under artificial lights. Run them seasonally, 11 hours in winter and 14-16 hours during the summer. The multifloral, strap-leaved species and hybrids can take strong light up to 2500 foot-candles. Maudiae and other mottled leaf Paphs prefer a bit less, around 1000-1500FC. If your mature plant is having trouble blooming, it is likely not getting enough light. A good indication of too much light, however, can be felt by touching the leaves. If they are hot to the touch, they are getting too much light and are at risk for burning.

Temperature
There are both warm and cool growing Paphs. The strap-leaf multiflorals and the mottled leaved plants generally like intermediate to warm conditions, 70-85° F. during the day and 55-65° at night. Cooler growing species such as tigrinum and fairreanum, as well as the complex hybrids bloom mostly during the winter season. They prefer temperatures around 65-70°F. during the day, and 55-62° at night.

Water
A good rule for Paphs is to always keep plants moist, never soggy, and never dry. Generally water once or twice a week depending upon the season. Use rainwater, distilled or reverse osmosis water, or tap water. Always water in the morning to ensure that the foliage will be dry by the evening and do not let water accumulate in the crown of the plant.

Humidity and Air Movement
Paphs prefer a humid environment. Between 50-70% is ideal. You can achieve this in the home by using humidity trays and by purchasing a home humidifier. Be sure not to set the pots directly in water, but above, either on a grid that fits inside the tray or on a bed of rocks or gravel. Air movement is also essential year round. A small fan near your growing area will help to keep air flowing and discourage rot or fungus from settling in.

Fertilizing
Recent research by Michigan State University has revealed that orchids generally need much less phosphorus to bloom than was initially thought. Since water quality is so important to the way plants utilize nutrients, they have developed two formulas—one for mineral-rich, or hard, water such as most well water (19-4-23), and a second for relatively pure water (13-3-15). Paphs do very well with MSU fertilizers, which are generally used at 1 tsp. per gallon of water once a week. Flush with clear water once a month to leach out any accumulated salts, which can burn the roots.

Potting
Repotting should be done generally every two years or before the growing media decomposes. Seedlings and smaller plants are often repotted every year. Paphs tend to do well in a variety of growing media, including combinations of fine fir bark, coconut husk chips, diatomite, and even semi-hydroponic inorganic media such as hyrdroton or Prime Agra. Repotting should be done when the plant is in active growth. Paph. roots can be fragile, so be careful when handling them.

 

[Heather]

Phragmipedium

Phragmipedium (frag-muh-PEE-dee-um) are the new world tropical lady slipper orchids with species originating from southern Mexico (Mexipedium xerophyticum) through central South America. Phrag. species are mostly found growing on the ground, on rocks, and occasionally in trees. The tree dwellers are the long-petaled species such as cadautum and its’ relatives, which are known to prefer dryer conditions than most other Phrags, which often grow in the splash zone of waterfalls and streambeds and can even be submerged during periods of heavy rain. Like Paphs, Phrags generally flower on every mature growth, usually in the late winter and spring, and mature plants can flower sequentially for many months. Phrags are also known to drop one pristine looking bloom just as another is ready to open. This just happens to be the way they flower. Hobbyists generally regard Phrags as the easiest type of slipper orchid to grow.

Light
Requirements for Phrags range from medium (1500-2000 foot-candles) for Phrag. besseae and its’ relatives, (which also provides the cooler temperatures they prefer) to bright (3000-4000FC) for the long-petaled caudatum types and xerophyticum.

Temperature
Most Phrags can be grown at intermediate temperatures with nights in the upper 50’s to mid 60’s. However, besseae and schlimii can tolerate and often prefer somewhat cooler temperatures. Phrag. besseae is known to bloom a brighter shade of red when grown on the cool side. The latest species discovered, Phrag. kovachii, is becoming known for not tolerating warm temperatures well. Closely related to the Phrags, Mexipedium xerophyticum prefers temperatures on the warmer end of the above range.

Water
Good quality water is very important for Phrags. Though tap water with low dissolved solids will be adequate, rainwater, distilled water, or reverse osmosis is preferable. Most Phrags should be kept moist all the time, with the exception of the caudatum types and xerophyticum which can be allowed to dry out a bit between waterings. Always water in the morning to ensure that the foliage will be dry by the evening and do not let water accumulate in the crown of the plant.

Humidity and Air Circulation
As with their Paph. relatives, Phrags prefer to grow in humid conditions. 50-70% is ideal. Constant air circulation is important in higher humidity growing areas so that plants do not become prone to bacterial rot. The long-petaled caudatum types are well known for being susceptible to this sort of problem.

Fertilizer
Feeding Phrags too heavily can cause leaf-tip burn. Be sure to occasionally flush the pots with clear water to avoid accumulating salts. A good rule of thumb is to fertilize at a half or quarter the recommended strength for three waterings, and then to flush with clear water every fourth.

Repotting
Phrags tend to be tolerant of repotting, which can generally be done every two years or when the mix has decomposed significantly. Since Phrags like it on the wetter side, mix can often decompose more rapidly than with a dryer growing orchid. The best time to repot is after flowering, when new growth emerges.