Orchid Care: Phalaenopsis

Phalaenopsis, or moth orchids, may soon be America’s favorite houseplant. Lavish sprays of pink, white, yellow, red, spotted or striped flowers, which remain fresh for many weeks, brighten the winter and spring scene. Although phalaenopsis flowers appear to be quite fragile, they are not at all hard to care for, and are considered to be ideal indoor orchids.


TEMPERATURE Phalaenopsis need to be warm all year, with daytime temperatures between 70–85°F and never below 60° during the night. During the autumn, keep them cooler for 4 to 6 weeks (around 60°F) to encourage flower formation.

LIGHT Provide an east (ideal), north, or shaded south facing window. Phalaenopsis need mostly shady light conditions during the summer and filtered bright (never sunny) conditions in the winter.

WATER Keep moderately moist all year round. The planting medium should never be allowed to dry out completely. Use only soft, lukewarm water. Never water the center of the plant as this brings the danger of rotting. Spray the leaves often to ensure that humidity is high - this is particularly important for phalaenopsis species. This is an orchid that will appreciate having its pot set on a dish filled with pea gravel or small stones, with water reaching the top of the gravel for extra humidity.

FERTILIZING It is important that phalaenopsis receive applications of diluted 20-20-20 fertilizer, especially in the spring and summer. In the autumn, switching to bloom booster fertilizer, coupled with cooler nights, induces plants to set buds and flower.

POTTING Phalaenopsis requires plenty of air around their roots. This means that you must definitely avoid waterlogging around the pots. For an adult plant, choose a coarse, air- and water-permeable medium such as medium-grade (1/2 to 3/8 inch) fir bark with a very small amount of peat, charcoal, and perlite or sponge rock. Repot every 14 to 18 months. High quality fir bark (without wood chunks) can last 2 years. Commercial orchid potting mixes are also available. Soak any potting medium overnight before planting. When repotting, choose a new pot only slightly larger than the old one.