How not to kill a Moth orchid
Common Name: moth orchid
Botanical Name: Phalaenopsis spp.
Plant Type: orchid, tropical herbaceous perennial, epiphytic
Mature Size: 8 to 34 inches x 12 inches
Origin: Southeast Asia, New Guinea, Indonesia, Philippines, north Australia
Hardiness Zone: 10 to 12
Foliage: overlapping in two rows originating from a single crown, leathery, oblong
Flowers: many individual long lasting flat flowers borne on long leafless stems
Fruit: pods contain countless tiny seeds
Exposure: bright shade, east window
Soil: bark chips potting media
Uses: houseplant, outdoor ornamental perennial in tropical climates
Propagation: seeds, keikis (plantlets)
Problems: mealybugs, scale insects
It’s really easy to grow orchids when you live in a tropical climate, but growing them as houseplants is tricky. I grew Phalaenopsis orchids outside in Florida by hanging them in the trees in my garden. They flowered regularly with very little care, however they had to be brought inside when the temperatures dipped to 40°F (4°C). They don’t like being too chilly.
Growing moth orchids as houseplants is a tad more difficult. After numerous failed attempts (sorry to all those dead orchids), I have learned a few things along the way.
One of the biggest killers of inside growing is overwatering. Yes, they like it humid but their roots will rot if they are kept too wet. Before adding any water, feel whatever they are growing in with your fingers. If it’s still moist, don’t water. Wait until it’s dry to the touch then add enough to water until it barely runs out of the pot. Keep water away from the crown (where the leaves join together). Blot any water away with a paper towel if it does. Use lukewarm water, not cold, as they are from the tropics after all. Don’t use salt-softened or distilled water either. Tap water left to sit overnight and rain water are ideal.
Phalaenopsis orchids are not sun lovers, even though they originate from tropical humid, lush jungles. They are not terrestrial, which means they don’t grow in soil but in tree canopies, so they are shaded from direct sunlight.
Phals do best in bright light, but not full direct sun. Leaves will turn white, silvery or a dark red. If the light is inadequate, the foliage may droop and becomes a deep green. An east facing window is perfect during the winter, however, it may become too strong in spring and summer. Just move them away from the window away from direct sunshine. West and south facing windows are suitable only if they are shaded with sheer curtains, or use blinds to direct the sun away. Another option is to grow them under grow lights, placed a foot away.
Since these types of orchids are epiphytic, they don’t grow in the ground; they cling to trees instead. Nutrients and water are absorbed from the air via their foliage and their ropey roots that also attaches to trees. They don’t hurt the trees, they just use them for a support.
To replicate their growing conditions, use an orchid growing mix. They are made with chipped Monterey pine, redwood or fir tree bark mixed with charcoal, perlite and/or coir (coconut husks). Oftentimes, orchids are grown in sphagnum moss, however it tends to retain too much water, which soon results in an overwatered orchid.
Temperature & Humidity
They prefer a warm household of 75 to 85 °F (24 to 30°C), but still do well at 65 to 75°F (18 to 24°C). The hotter it is, the more humidity and air flow is needed. Stagnant air leads to diseases and fungi. Don’t crowd them together, and if you have many orchids, use a gentle fan to move the air around. Where the air is dry, increase the humidity by placing orchid on a shallow tray of pebbles topped with water. The roots should not sit in the water. Misting a few times a day is also beneficial.
In September to October apply orchid fertilizer to encourage flowering. Use a mister with fertilizer at half strength mixed in and spray on the foliage. This mimics their native habitat where they are nestled in jungle canopies. Use this misting method throughout the year.
More Flowers Please
It’s so exciting to see a new flower spike appear. To encourage flowering, ensure there’s adequate light. If it’s too shady the leaves will be green and healthy. Cooler night 55°F (13°C) also stimulates flowering. The contrast between day and night is key for new flowers to form.
When the flowers fade, cut the green stems back, but not quite to the base. Keep two to three nodes. They are the small brown lines on the stem. In a few months a new flower spike will grow out of the old one.
It’s time consuming growing orchids from seed, so when a flower spike produces a plantlet, known as a keiki on the flower stem, it is a perfect opportunity to grow this clone on. Allow it to mature on the stem for a year. It should have two to three leaves and have a nice set of roots about 3 inches long. Gently remove it from the parent plant and place it in a pot with orchid potting mix. Generally it takes up to 3 years for a keiki to blossom