With their large, exotic blooms, usually in shades of pink, white or yellow, and with an array of flower forms and patterns, Phalaenopsis, or moth orchids, are popular houseplants. They’re easy to grow, can flower for several months and with the correct care, will repeat flower and last for years.
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Today, you can pick up a moth orchid at the supermarket, so it’s hard to imagine that the cultivation of orchids was once the domain of the aristocracy. The discovery of the genus Phalaenopsis, which was easy to breed and grow, changed that.
Jump to:
- Moth orchid care
- What is a moth orchid
- How to look after a moth orchid
- How often to water a moth orchid
- How to repot a moth orchid
- The best moth orchid varieties
- Where to see and buy moth orchids
Phalaenopsis was first described in 1825 by the Dutch botanist Carl Ludwig Blume on the Indonesian island of Nusa Kambangan near Java; it is said that during one of his expeditions, he noticed what he thought was a group of butterflies floating motionless among the trees.
If you want to grow a moth orchid, it pays to know that they hail from tropical climates and are epiphytes
John Lindley named two species in his Gardeners’ Chronicle of 1848, which were Phalaenopsis rosea (now Phalaenopsis equestris), the ‘pink butterfly plant’ introduced by collector Thomas Lobb from Manila through Veitch’s Nursery; and P. grandiflora (now Phalaenopsis amabilis), with white, fragrant flowers.
Moth orchids soon became more popular than the previous favourite, the Cymbidium orchid, which only flowered once a year, had grassy foliage that looked dull for most of the year and took up too much space. Phalaenopsis were more compact, flowered for months and were tolerant of a wider range of conditions, and soon became staple houseplants for every home.
Fact file: What is a moth orchid
- What: Popular and widely grown, repeat-flowering, exotic houseplants in the genus Phalaenopsis. Common name: moth orchid. Season Flowering intermittently year
- round, depending on cultivation techniques.
- Size: Variable but no more than 60cm x 30cm.
- Conditions: Phalaenopsis are epiphytic plants, meaning they grow in the wild on the surface of trees rather than in the soil, and should be grown in a proprietary orchid compost or bark chunks. They need bright, indirect light, tolerating some shade, constant temperatures and free-draining compost. Moderate humidity is preferable.
- Origins: Southern Asia, from Assam to Japan, including
- the Philippines and as far south as northern Australia.
- Hardiness: RHS H1A, USDA 10a-12.
Moth orchid care
If you want to grow a moth orchid successfully at home, it pays to know that they hail from tropical climates and are epiphytes, found perched on accumulations of organic matter on rocks and trees.
Their aerial roots absorb moisture and nutrients from rainfall, the atmosphere and water filtering through the organic matter above. Plants growing under the jungle canopy in deep shade are far more robust than those found in bright sun.
Mimic these conditions by growing your moth orchid in bright light, where it receives some direct sunshine in the early morning or late evening – a windowsill is ideal.
How to look after a moth orchid
Temperatures should be as consistent as possible – 20-30°C during the day and 15-20°C at night. Ideally, you should even transport your new moth orchid from shop to car in a protective sleeve, particularly in cold weather. Grow Phalaenopsis in proprietary orchid compost or bark chunks. These allow airflow around the roots, improve drainage and prevent root rot.
How to grow Phalaenopsis
Grow in bright light in a spot that gets a little direct early morning or late evening sun. A windowsill is ideal. Keep away from radiators and draughts, and bring in from behind curtains at night; low temperatures can cause buds and flowers to drop. Plants withstand temperatures down to 10-12oC but a minimum of 15oC is ideal.
Few houseplants can compete with the showiness of a moth orchid, so complement their beauty with ferns
Grow in an orchid compost or in 50mm to 1cm bark chunks to allow airflow around the roots, improve drainage and prevent rot. Clear plastic pots make it easier to check the colour of the roots – green roots are hydrated, while silvery ones need watering – and can be hidden in an outer ornamental pot.
How often to water a moth orchid
Water regularly rather than wait for the roots to dry out and change colour. Brown dead roots can be snipped off and there is no harm in trimming roots when repotting. Both roots and leaves photosynthesise so green tints to the roots are not a cause for alarm.
Water around every two weeks from spring to autumn, then reduce in winter. Tepid rainwater is preferable but they will tolerate tap water. Trickle water into the top of the pot to moisten the bark and roots, avoiding the ‘crown’, then allow to drain. Or plunge in water for ten minutes, shake away excess or allow to drain. Never let them stand in water. Many people kill orchids by overwatering.
Feed during the growing season with a specialist orchid feed or half-strength houseplant feed. Omit the feed every fourth watering to flush out excess salts.
How to repot a moth orchid
Re-pot at any time of year, but only once a plant is too large for its container or when the compost decomposes – usually after around two years. Roots growing outside the pot are simply replicating growth in the wild. Pots full of roots also prevent overwatering in winter.
Plants flower at least once annually, and last for years, so don’t bin plants after flowering. Sacrifice the last flower and cut the main flowering stem to just above the third or fourth node.
Keep at around 5oC lower for a month; this will hopefully encourage a secondary flower spike with new flowers. Only do this once, because trying again will stress the plant. Alternatively, cut the stem down to below the last bud. This allows the plant to recover so the new flowering spike is much more vigorous, with larger, longer-lasting blooms.
Dryness at the roots causes flaccid leaves. Existing leaves may not recover but fresh new leaves emerge after watering. White, fluffy mealybugs at the leaf bases need to be dealt with promptly. The RHS Orchid Committee advises picking these off by hand. You could also try an environmentally friendly spray.
The best moth orchid varieties
Phalaenopsis Puppy
The bright-white flowers of this compact orchid have daintily golden speckled centres that are held above glossy green leaves. Height and spread: 40cm x 30cm. AGM*.
Phalaenopsis Perceval
This agreeable compact Phalaenopsis displays large flowers striped purple-pink with a dark- purple lip. It is very floriferous with remarkable ‘flower power’ for a small plant. 33cm x 30cm. AGM.
Phalaenopsis Violet Queen
This eye-catching selection has faintly striped violet flowers and a darker, rich- violet lip. Good for growing in groups or as a feature plant where space allows. 29cm x 28cm. AGM.
Phalaenopsis Anthura Modena
This vigorous plant displays large lemon-yellow flowers with raspberry-speckled centres. Ideal against a plain background where the minute detail in the flower becomes prominent. 54cm x 33cm.
Phalaenopsis Safe Haven
An understandably popular and extremely attractive orchid, whose simple white flowers with a deep-purple lip and intricate, orange- speckled centre create
a highly desirable and appealing colour combination. 33cm x 30cm.
Phalaenopsis Dover
An elegant plant with large mid-green leaves and plain white flowers with a yellow lip and mauve at the throat. It is very floriferous, often displaying three unbranched flower spikes. 50cm x 35cm. AGM.
Phalaenopsis Sunny Shore
The pale-yellow and white flowers of this elegant orchid are spaced attractively along the flower spike, which is positioned above elegant upright leaves. 32cm x 24cm.
Phalaenopsis New Life
An elegant fusion of white, pink and yellow flowers. Breeders have replicated wild plants with a scent that can only be detected just after sunrise on warm days for around an hour. 32cm x 33cm. AGM.
Phalaenopsis Anthura Denver
With large mid-green leaves and branched flower spikes, it creates an elegant floriferous display producing a mass of white flowers, which are faintly striped purple and have a purple lip. 60cm x 40cm. AGM.
Phalaenopsis Birdie
Producing masses of buds and flowers, this compact, multi-stemmed hybrid has pink-striped flowers with a plain mauve lip and yellow throat held at the top of the flower spike, and elegant leaves. 27cm x 27cm. AGM.
Phalaenopsis Anthura Salta
A floriferous plant with striped purple-pink flowers and a plain purple lip marked yellow at the throat. Multi-branched, it creates a pleasing effect as a single specimen. 31cm x 20cm. AGM.
Where to see and buy moth orchids
- Burnham Nurseries Forches Cross, Newton Abbot, Devon TQ12 6PZ. Tel: 01626352233, orchids.uk.com
Laurence Hobbs Orchids Bailiffs Cottage Nursery, Hophurst Lane, Crawley Down, West Sussex RH10 4LN. Tel 01293 561029, laurencehobbsorchids.co.uk - Love Orchids loveorchids.co.uk
- The Glasshouse, RHS Garden Wisley, Wisley Lane, Woking, Surrey GU23 6QB. Tel 01483 224234, rhs.org.uk/gardens/wisley
