Information on Phalaenopsis

 

Phalaenopsis (fail-eh-NOP-sis)genus often called the Moth Orchid comprises about 50 monopodial epiphytic and sometimes lithophytic species, found in southern India and Nepal, China, Philippines, Papua New Guinea and northern Australia.  These areas experience little variation in temperature and a distinct wet and dry season.  They are closely related to Doritis.  These plants have very short stems with broad fleshy leaves and many thick roots.  Inflorescences emerge from between the leaves and may have a few to over 100 flowers.  The flowers can last 3 months or more.

 

Temperature: Warm temperatures are required at  all times.  A minimum temperature of 10ºC to 15ºC is recommended.

 

Light: Phalaenopsis require a minimum of 70% shade in winter with additional shade in summer.  Too much light bleaches the leaves and can cause sunburn.  A medium green leaf colour indicates the right light.

 

Air Movement: Gentle air movement helps to prevent disease and it also helps to keep leaf temperatures low.  If the light is too bright, air movement will help to prevent sunburn.

 

Humidity: Phalaenopsis require high humidity, which can be achieved by keeping the shadehouse floor damp during the hotter part of the day.  Over watering leads to root-rot.

 

Watering: Phalaenopsis like to have their roots damp, but not wet.  If an open type potting mix is used (bark, charcoal, coconut husk chunks, etc) water every 2 – 3 days in summer and extend to weekly in the winter.  If a potting mix of sphagnum moss or a mix of mostly sphagnum moss, water every 5 – 7 days in the summer and 10 – 12 days in winter.  Remove any water from the crown of the plant late in the day, to prevent crown rot.  A drinking straw can be used to blow away any left over water.

 

Fertilizing: Fertilize at half the recommended strength at each watering, as these plants have no rest period.

 

Pests & Diseases: Phalaenopsis are susceptible to bacterial and fungal diseases.  The pests that cause the most trouble are cockroaches and snails on the flowers and roots, with mites on the leaves. Remove infected leaves with a clean razor blade and immediately seal with ground cinnamon (from kitchen cupboard) or fungicide powder.

 

Repotting; Repot mature plants every 18 to 24 months, seedlings and small plants every 12 to 18 months. Take the plant from pot; remove potting material and any dead roots. Remove the bottom of the plant, below the healthy roots, so that it fits into the pot with the lower leaves, just below the top of the pot and seal the cut. After spraying roots, to make them flexible, cut off any excess length, so that plant fits in the pot. Most are potted in one or combinations of the following; bark, charcoal, coconut husk chunks, Perlite and Sphagnum moss. Best time to repot is September/November, small plants September to March.