Orchids as Houseplants: What Actually Works

More orchids are killed by kindness than by neglect, and almost always by the same mistake: watering them like a normal houseplant. An orchid is not growing in soil, and treating the roots as though it is will finish it within a few months.

They Are Epiphytes

Most orchids sold as houseplants — Phalaenopsis above all — grow naturally on tree bark rather than in the ground, with roots exposed to air, wrapped around branches, drenched by rain and then dried by moving air within hours.

Those roots are covered in velamen, a spongy tissue that absorbs water fast and then seals. It is built for intermittent soaking, not constant moisture.

Which is why they are potted in bark chips rather than compost, and why a pot that stays wet rots the roots. Root rot is the single commonest cause of death, and it is invisible until the plant collapses.

Watering, Properly

Forget schedules. Look at the roots, which is why orchids are sold in clear pots.

Healthy hydrated roots are green and plump. When they need water they turn silvery-grey. That colour change is the instruction, and it is far more reliable than any weekly routine.

When they do go grey, water thoroughly — run tepid water through the bark for a minute or take the inner pot to a sink and let it soak briefly — then let it drain completely. The pot must never stand in a saucer of water.

Depending on your home this typically works out to every seven to fourteen days, and it changes with the season. Ice cubes, which circulate as advice, are a poor idea: these are tropical plants and cold damages the roots.

Light

Bright and indirect. An east-facing window is close to ideal, or a few feet back from a south or west one.

The leaves tell you. Healthy Phalaenopsis foliage is a mid grass-green. Dark green means too little light, which is the usual reason a plant lives for years and never flowers again. Yellowish or red-tinged means too much, and direct summer sun will scorch them.

Different genera differ substantially. Vanda needs very high light. Paphiopedilum, the slipper orchid, is a low-light plant that the bright position a Vanda wants would burn. Cymbidium is cool-growing and wants a marked night-temperature drop to flower at all.

Getting It to Flower Again

The question we are asked most, and the answer is usually temperature rather than feeding.

Phalaenopsis initiates a new flower spike in response to a drop in night temperature — roughly 10°C cooler at night than by day, for two to four weeks. In a house held at a constant temperature year-round this never happens, and the plant simply grows leaves.

Putting it somewhere cooler at night in autumn, or near a window where the temperature naturally falls, is what triggers the spike.

Feed weakly and often during active growth — a dilute orchid fertiliser at a quarter strength every second or third watering, and flush with plain water periodically to prevent salt build-up in the bark.

After the Flowers Drop

Do not throw it away, which a great many people do.

On a Phalaenopsis, if the spike is still green, cut it back to just above a node partway down and it will frequently branch and flower again from that point. If the spike has gone brown and dry, cut it off at the base and let the plant put its energy into leaves and roots for the next cycle.

Repot every couple of years into fresh bark. Old bark breaks down into something that holds water like compost, which returns you to the root-rot problem.

The Cut-Flower Alternative

Worth saying plainly: if what you want is orchids in the room rather than a plant to keep, cut orchids are a genuinely good buy.

Cymbidium holds four to six weeks in a vase, Vanda two to three, and slipper orchids four to eight. That is longer than most people manage to keep a Phalaenopsis flowering, with none of the husbandry.

For a desk or a reception where the requirement is that it always looks correct, our Orchid Presence — Classic does that job on a cycle of weeks rather than days. And for someone who does want the plant, our Orchid Presence — Statement is the version worth keeping alive.

The Genera Worth Trying Next

Phalaenopsis is the beginner's orchid for good reason, and three others are worth knowing once it stops being interesting.

Dendrobium is nearly as forgiving, tolerates lower humidity, and carries flowers along an upright cane rather than an arching spike.

Oncidium — the dancing lady — produces sprays of many small flowers and wants slightly more light and more frequent watering.

Paphiopedilum, the slipper orchid, is the one most often recommended wrongly. It is a terrestrial rather than an epiphyte, so it wants a coarse open compost that stays evenly moist rather than drying hard between waterings, and it is a low-light plant. Somebody who has killed a Phalaenopsis by overwatering will find it more forgiving, not less.

Two Things That Are Not Problems

Aerial roots wandering out of the pot are normal and healthy. Do not bury them; that is what epiphyte roots do.

And a wrinkled leaf usually means underwatering or damaged roots rather than a need for misting. Misting does very little for orchids in a normal home and can encourage rot in the crown, which for Phalaenopsis is fatal.