In cultivation for hundreds of years, Phaius is a genus of about 50 species of large, warm-growing, terrestrial orchids found in a huge natural range including Africa, Madagascar, Asia, Australia, and the Pacific Islands. Phaius tancarvilleae (Nun’s Orchid) is the species most often found in commerce. Easy to grow in the home, as long as you follow an appropriate care routine, these orchids are spectacular plants and make gorgeous houseplants.

Phaius orchids are sympodial in growth habit (they produce multiple stems). They are robust species with very short rhizomes and rounded fleshy pseudobulbs. Each pseudobulb is enclosed by 2 to 8 large, thin, deeply grooved leaves, up to 4 ft. long (120 cm).

The flowers are borne on basal or axillary inflorescences. Often very showy and distinctive, with entire or lobed lips, the blossoms appear in a variety of colors on straight stems rising to as much as 4 ft. tall (120 cm). They turn blue-black when damaged or as they fade.

Growing Phaius Orchids

Light
Phaius orchids are easily grown in a well-drained but humus-rich compost in bright light to light shade, but not direct sun. If the leaves become dark green, your orchid is probably not getting enough light. If the leaves become yellow, your orchid might have been exposed to too much sunlight. Provide supreme air circulation year-round to prevent Botrytis fungus.

Temperatures 
Phaius orchids require intermediate to warm temperatures between 60-70°F (15-21°C).

Water 
Keep your Phaius orchid evenly moist year-round, except when new growth has matured. When new growth has matured, the plant should be left to dry out for 3 to 4 weeks. Water in the morning and avoid wetting the leaves. 

Humidity
Maintain adequate humidity (50%) for most of the year by standing your container in a tray of damp pebbles.

Fertilization
Provide regular fertilization. Fertilize once a week after watering. Use half-strength applications. It is important to flush with clear water to remove excess fertilizer, which can burn roots.

Potting
Repot after flowering, splitting growth into four pseudobulbs per pot.

Pests and diseases 
Phaius orchids are generally disease free. Keep an eye out for aphids, glasshouse red spider mites, mealybugs, and root rot (excess moisture).