Phalaenopsis stuartiana (Moth Orchid)

Phalaenopsis stuartiana (Moth Orchid) is an evergreen, epiphytic orchid boasting up to 100 long-lasting, faintly scented flowers, 2-5 in. across (5-10 cm). Blooming in the winter and spring, the flowers feature wide creamy-white upper petals, sulfur-yellow lateral sepals, and lips with brown spots. The showy blossoms are borne on a branching inflorescence, 36 in. long (90 cm). The elliptic-oblong leaves, up to 18 in. long (45 cm), are dark green mottled with silver gray above, flushed with purple underneath. Native to the Philippines, Phalaenopsis stuartiana can be found growing in lowland forests at elevations up to 1000 ft. (300 m).

• Grows up to 24-36 in. tall (60-90 cm).
• Grow in an open bark-based compost and position with good indirect light. An east or west window would be ideal.
• Needs a minimum night temperature of 70-73°F (21-23°C) and a daytime temperature of 84-86°F (29-30°C) in summer.
• Needs a minimum night temperature of 70-71°F (21-22°C) and a daytime temperature of 80-84°F (27-29°C) in winter.
• Fluctuating temperatures can cause bud drop on plants with buds ready to open.
• Maintain high humidity (55-70%) for most of the year by setting the plant on a tray of gravel, partially filled with water, so that the pot never sits in the water.
• Water moderately throughout the growing season. The plant should be constantly moist. Avoid letting the plant sit in water. Mist the plant lightly in summer.
• Water only in the morning, so that the leaves dry by nightfall. This will prevent rot.
• Feed once a week or once every two weeks during the growing season with a special liquid fertilizer for orchids, taking 1/4-1/2 of the dose indicated on the vial.
• Propagate by division. Cuttings or offshoots may be rooted successfully when roots are 1 in. long (2.5 cm).
• Once the flowers have faded, cut the flowering stalk back to just above the second node (joint) visible beneath the spent flowers. A new flowering side shoot may develop.
• Phalaenopsis can be repotted at any time of year. The best time to repot is when new roots with green tips emerge at the base of the plant.
• To repot, remove all the old medium from the roots, snip off any diseased or dead roots, and spread the remaining roots over a handful of medium in the bottom of a new pot. Fill the rest of the pot with medium, working it among the roots, so that the junction of the roots and the stem is at the top of the medium. Gently ensure the compost is pressed down firmly around the perimeter of the pot. Drain the plant thoroughly and do not allow it to sit in water.
• Generally disease free. Keep an eye out for aphids, glasshouse red spider mites, and mealybugs.
• Native to the Philippines.

Tip for reblooming

• If a plant is large and healthy but does not produce flowers in a reasonable time, then reduce the temperature by 8°F (5°C) for four weeks, and a flower spike will usually develop.