Cultural Notes for Phalaenopsis Orchids

Phalaenopsis orchids have become popular as house-plants due to their ease of culture and beautiful, long-lasting flowers. The name, Phalaenopsis, means “moth-like”, and in their native Philippines the wild species are said to resemble flights of moths in the jungle. Modern Phalaenopsis hybrids are very colourful and can be found in white, yellow, pink and with spots and stripes. The wedding favourites are the large white flowers with yellow on the lip. These flowers will last for months with proper care. When the first spray of flowers is over, cutting the stem just above the third or fourth node can sometime initiate a side stem giving more flowers. This should only be done when plants are in good health and growing vigorously. Small plants should have their blooms removed after about 6 weeks to encourage growth for the next year’s blooms.


Phalaenopsis can be grown indoors as house plants and need good light to do their best. Morning light is better than the hot afternoon sun and protection should be given against the sun’s direct rays burning the leaves through a glass window. They will be happy at any temperature that is comfortable for humans. They want warm temperatures in winter and must not be put outside.


During the warm growing season the plants require plenty of water. Water well at least once a week if in a bark mixture, if in sphagnum moss, I suggest watering only once in 10 – 14 days (normally these plants are in a clear plastic container). For non-booming plants feed every second watering using a high nitrogen feed such as Starke Ayres ‘Growing Orchids’ formula from September to January. From January switch to the Flowering Orchids formula to help initiate the flower spikes. All fertilizers should be used at half the recommended application. Reduce water and feed at the onset of the cooler months. Luke warm water is best in cold winter months.


I suggest that all Phalaenopsis planted in sphagnum moss be repotted into Outeniqua Seedling bark mix after flowering. This mix contains all the plant’s needs including bonemeal and dolomite lime. Remove plant from container. Remove all sphagnum moss from around roots (or any other mix it may be planted in). Cut off dead roots. Reduce length of live roots by at least a third. It can be repotted in the plastic sleeve if it fits, otherwise a larger pot may be required. Place the plant in the pot and fill in the damp mix tapping the sides gently to make sure the mix reaches the bottom. Water well when complete. If roots are not in good condition reduce watering until the new roots can be seen.


A shallow tray containing stones and water, aids in surrounding the plants with much needed air moisture. An alternative to this is to spray the leaves in the morning on sunny days only. Foliage must be dry by nightfall. Plants must not stand in a tray of water like an African violet.


If unsightly spots appear on the leaves use a fungal spray about once a month on the top and underside of the leaves. Fungi Gun is quite useful for this. If you spot a woolly insect (mealy bug) around the flowers or leaves, a simple remedy is to dip a cotton bud in methylated spirits and dab on the insect, it dies instantly.