Botanical name: Phalaenopsis spp
Moth Orchids also called Phals are popular Indoor Orchids that are easy to grow. They bear flat-faced, fragrant, long-lasting flowers on a stem that often branches near the end. The flower sepals and petals are all free and widely apart from each other. The petals are are much wider than the sepals. The lip (lowermost petal) is significantly different from the other petals and has three lobes. Several of the flat-faced flowers blooming along an arching stem look like moths in flight and hence the common name, "moth orchid". Moth Orchids are monopodial. These are plants which grow from a single point, they add leaves to the apex each year and the stem grows longer accordingly. They have long-coarse roots and short, leafy stems hidden by overlapping leaf bases; they do not have pseudobulbs. The leaves are dark-green on top with streaks of red or burgundy on the the undersides. They are usually arranged in two rows, relatively large and leathery, oblong and sometimes succulent. Phalaenopsis is a genus of orchids occurring in the wild from tropical to subtropical Asia with the majority in Indonesia and Philippines where they grow on trees. The genus name Phalaenopsis is derived from the Greek word phalaina meaning "a kind of moth" in reference to the moth-shaped flowers. The genus name is abbreviated as "Phal" in horticultural journals. Many hybrids and cultivars have been developed. Flowers are available in red, white, pink , yellow and purple and sometimes spotted and often with a contrasting lip and veins.
Moth Orchids grow best in bright, indirect light for about 10 hours per day. A few feet away from an east- or west-facing window is ideal. Keep them away from direct sunshine to avoid scorching the leaves. Regularly turn the pot to ensure the plant gets adequate light on all sides. A Moth Orchid that is receiving the right amount of light has dark-green leaves. Yellow leaves means the orchid is receiving too much light. Learn how to ensure your plant receives the correct light in this guide on understanding light for houseplants
Water Moth Orchids thoroughly during the growing season and allow the top half of the soil to dry out between waterings. Reduce watering in the cold period. To take the guesswork out of watering Moth Orchids, check the color of roots. Whitish-green and plump roots indicate the orchid is well hydrated. Whitish-silvery roots indicate the orchid needs to be watered. Use tepid, chlorine-free water as orchids are sensitive to chlorine and other chemicals dissolved in water. Avoid wetting the foliage as it can lead to fungal diseases. Moth Orchids are less tolerant of dry soil conditions due to the absence of pseudobulbs. Learn more on how to water houseplants.
The best temperatures for Moth Orchids are between 10-290C. Warmer days and cooler night temperatures with a difference of 10-150C are ideal. Cool nights are essential to trigger flowering. Ensure there is good air circulation as orchids cannot tolerate hot and stuffy conditions. Protect them from draughts. Learn more on temperature for houseplants.
Moderate humidity is ideal for Moth Orchids. If the air is too dry, set the pot on a wet pebble tray to raise humidity. Occasionally clean the leaves by damp-wiping with a soft cloth. Do not mist the leaves as it can lead to fungal diseases.
Feed Moth Orchids every 2 weeks during the growing season with a balanced water-soluble fertilizer. Withhold feeding during the cold season. Do not feed an orchid that is in flower. Learn more on how to feed houseplants.
Repot Moth Orchids only when growth begins to suffer, the lower leaves begin to die. They bloom best when they are pot-bound. Basically repotting Moth Orchids every 2 years should be adequate. Repot only when new growth begins, shortly after blooming is over. Do not repot an orchid that is in flower as it may shorten the flowering season. Use a pot with proper drainage holes or slits; the roots need good air circulation. The pot should be only 1 size larger than the previous one. Use loose, free-draining bark soil. While repotting, remove all the soil from around the stems and roots. Remove any dead and dying leaves from the bottom of the plant. Remove dead roots to create space for the growth of new roots. Water the orchid thoroughly and ensure that both the soil and the roots absorb all the water they need.
Pruning Moth Orchids is easy. Remove dead and diseased leaves by cutting them at the base with sharp scissors or a knife. When flowering is over, cut the flower stalk 1 in. above the 3rd node from the bottom.
Propagating Moth Orchids from keikis
Moth Orchids are propagated from keikis. These orchids naturally produce "baby" orchids called "keiki" which normally appear on an old or new flower spike or at the base of the orchid. Keikis are identical copies of the parent plant. Keiki growth can be triggered by prolonged exposure to high temperature during the final phase of spike growth. The keiki can be detached from the mother when about one year old when it has developed 2-3 leaves and 1-3 in. long roots. Pot up the keiki in fresh potting medium. Direct the roots downwards and provide support for the keiki. Place the set up in a shaded place. Mist the keiki regularly to maintain a humid enviroment. The keiki may take 6-12 months to bloom.
Brown soft spots on Moth Orchid leaves are an indication of a fungal disease; remove the affected leaves immediately to prevent further spread.
Exposure of Moth Orchids to direct sunshine will result in scorch marks which are brown hard and dry spots on the leaves. Move the orchid to a shadier spot or protect it from direct sunshine.
This is an indication of Powdery Mildew Disease. Misting the leaves in Moth Orchids may lead to mildew growth if the water does not evaporate quickly. Ensure good air circulation and stop misting.
Limpy and droopy leaves in Moth Orchid are caused by underwatering. Do not allow the soil to dry out completely. Water Moth Orchid thoroughly, maintain the soil consistently moist and allow only the top half of the soil to dry out between waterings.
Too little light for Moth Orchids will result in no blooms. Move the orchid to a brighter spot. Moth Orchids bloom best when grown under bright, indirect light.
Yellowish leaves in Moth Orchid indicate that the plant is getting too much light. Move the orchid to a shadier spot. The leaves of a Moth Orchid that is receiving the correct light should be dark green.
The cause of black leaf tips in Moth Orchid is the presence of chemicals like chlorine and flourides in water. Use chlorine-free water only.
Moth Orchids (Phalaenopsis spp) are non-toxic to both humans and pets. They are safe to grow indoors.