Updated: Feb 5
Orchids in the genus Paphiopedilum are some of the easiest to care for, and they produce beautiful, long-lasting blooms. Let’s learn about these attractive plants. There are about 80 species and hundreds of hybrids in the Paphiopedilum genus. Some have striped or variegated leaves, and others have flowers with spots, stripes or patterns. Many of these varieties are prized by collectors.
Paphiopedilums are often called "slipper orchids" because of their unique pouch. However, they are different from the North American wildflowers known as lady’s slipper orchids. Most Paphiopedilum species are terrestrial orchids, which means they grow in soil. Terrestrial orchids should be grown in a pot, not in a hanging mount as is sometimes used for tree-dwelling epiphyte orchids. Growing Paphiopedilum terrestrial orchids outdoors is also possible in tropical and subtropical climates.
These Southeast Asian plants have flowers of heavy substance, lasting from one to three months. There are multi-flowered, sequential flowered and single flowered varieties of many different sizes, shapes and colors.
Paphs belong to the "low" light group of orchids. Place in any bright window but protect from midday sun. Leaves should be a medium-green color. If they are too pale or yellowish, the plant could be getting too much light.
An east window is ideal; west or south windows can also be used if shaded with a sheer curtain. You can tell by the leaves if the plant is getting too much light. A reddish tinge on the edges means you need to provide more shade for your plant. If your paph does not re-bloom, it may not be getting enough light.
Paphiopedilum are divided into two temperature groups: warm and cool growers. The attractive mottled-leaf types come from the temperate zones and the solid green-leafed types come from the higher, cooler altitudes.
Generally speaking, those with mottled foliage and the strap-leafed, multi-flowered species or hybrids do best in intermediate to warm conditions, preferring daytime temperatures of 21-26º C and nighttime temperatures of 13-18º C. The cool-growing species are mostly from India and grow at higher elevations. Complex hybrids are cool growing and bloom mostly during the winter season. These types prefer nighttime temperatures of 13-17º C with days around 18-21º C. They will all tolerate the heat of summer as long as they are regularly watered, shaded and kept in humid conditions. The mottled leaved varieties do best in a warmer house or apartment and can often bloom twice a year.
Keep in mind that temperatures close to the window on a windowsill will be colder or hotter than your general house temperature. Paphs can be grown outside in mild climates. Protect plants during cold temperatures by avoiding moisture on leaves or in the crowns and in summer from burning from the sun.
“ Know the Origin of your Species or Hybrid before setting Temperature”
How often you water will depend on whether your plant is potted in bark or a sphagnum moss mix and the amount of light and heat. Paphs need more frequent watering than some other orchids because they have no pseudobulbs to store water. Bark retains less water so will require more frequent watering - every two days is usually sufficient. If your plant is potted in moss, water when the top feels dry. Care should be taken not to overwater to avoid rotting the roots. Soon you will be able to tell by the weight of the pot whether or not it is time to water again. If in doubt, wait a day.
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. Like all orchids, it is important to water in the morning. This insures complete water evaporation on the foliage as well as the crown by nightfall, thus preventing bacteria and fungus rot. Water the plant as it approaches dryness. Use rainwater, distilled water, reverse osmosis water or municipal water. Do not use softened water. Put plant in sink when watering and allow it to drain well. Under most growing conditions, watering is done at 3-7 day intervals depending on the pot size.
"PLANTS SHOULD NEVER STAND IN WATER!"
Paphs like a humidity of between 45% and 70%. This may be accomplished by the use of humidifiers or by filling a saucer with crushed rock and placing it under the plants. The water under the rock will slowly evaporate, slightly raising the humidity level. Be sure the pot does not sit in water as this will rot the roots. DIY humidity trays are another option you can use to place your plants on.
Give your plants room for air to circulate around them. Crowding of plants can lead to problems with insect infestations and fungus. A small fan will help provide good air circulation around your plants.
They mostly flower in spring, early summer or early autumn but in the right conditions can flower year round. The flowers are small to large and are highly specialized to attract specific insect pollinators and many have a strong pungent odor to attract mainly flies.
Fertilize on a regular schedule, but care must be taken to avoid burning of the fleshy, hairy roots. High-nitrogen fertilizers are recommended when potted in any fir-bark mix. It's important to flush with clear water monthly to leach excess fertilizer, which can burn roots. In cool weather, fertilizer applications once a month are sufficient.
Balanced Fertilizer for Growth: 20-20-20 (NPK) – 1 gram per litre of water – Spray once in every alternative weeks (14 Days)(Only on Warm Seasons)
High-Nitrogen Fertilizer for Blooming: 30-10-10 (NPK) – 0.5 gram per litre of water – Spray on every Week (All Year Round)
Potting , Media and Propagation
Potting should be done about every two years, or as the medium decomposes. Seedlings and smaller plants are often re-potted annually. Mixes vary tremendously; most are fine- or medium-grade fir bark, with varying additives, such as perlite (sponge rock), coarse sand and sphagnum moss. Moisture retention with excellent drainage is needed. Large plants can be divided by pulling or cutting the fans of the leaves apart, into clumps of three to five growths. Smaller divisions will grow, but may not flower. Spread the roots over a small amount of medium in the bottom of the pot and fill with medium, so that the junction of roots and stem is buried 1 to 2 inch deep in the center of the pot.
When the blooms are finished, cut the spike down to the level of the leaves. Continue watering and fertilizing and within a year a new growth will spike to begin the blooming cycle again! When the plant has finished blooming is a good time to repot your orchid.
“Most growers find that plastic pots work best for Paphiopedilums”
Pests and Other Paphiopedilum Related Problems
Fungal and Bacterial Diseases of Paphiopedilums are common because of the levels of humidity they need to survive. Fungal agents cause problems like root rot, leaf spots, leaf blights and distortion in flowers.