How to Care for a Phalaenopsis Orchid and Get It to Rebloom

The Phalaenopsis wants plenty of light, but indirect. The direct midday sun scorches the leaves, leaving yellowish patches or dry areas. The ideal spot is in front of an east-facing window, or a west- or south-facing one filtered by a light curtain. North-facing windows are usually too dark for it to rebloom.

A good indicator is the colour of the leaves: a light grass green signals correct lighting, while deep dark green leaves often mean the plant is getting too little light to produce flowers. Yellowish or scorched leaves, on the other hand, mean too much sun.

Temperature

It does well at household temperatures, roughly 18 to 29 degrees, as long as nights don't drop below about 15. A warm room in summer is no problem if the air isn't too dry. Avoid cold draughts and, in winter, being right next to radiators, which dehydrate the plant and its flowers. As we'll see, a slight difference between day and night is exactly what triggers reblooming.

The most common mistake with orchids is overwatering. The Phalaenopsis is an epiphytic plant: in the wild it lives clinging to trees, with its roots exposed to the air, and it rots easily if left in stagnant water.

When to water

There is no fixed calendar: it depends on light, temperature and growing medium. On average you water every 7–10 days, but the real signal comes from the roots and the weight of the pot. Wait until the medium (usually bark) is nearly dry and the pot feels light when you lift it.

The silvery roots

This is the single most useful detail. Healthy Phalaenopsis roots turn green when well hydrated, while as they dry out they turn a silvery grey. Silvery roots mean the plant is thirsty; bright green roots mean it still has enough water. Learning to read this colour is the most reliable way to avoid mistakes.

How to water

The best method is soaking: sit the clear inner pot in a basin of room-temperature water for about 10–15 minutes, then let all the excess water drain thoroughly before putting it back in the cachepot. Water should never be left sitting at the bottom. Wet the medium, not the crown of the plant where the new leaves form: water lingering there can cause rot.

The Phalaenopsis is not grown in ordinary potting soil, which suffocates the roots. It wants a coarse, airy medium, usually pine bark, often with a little sphagnum moss or draining materials.

The clear inner pot isn't just for looks: it helps you check the colour of the roots and lets a little light through, since the roots are photosynthetic. Choose one with good drainage holes.

Humidity

These orchids like slightly humid air, roughly 50 to 80%. Indoors, especially in winter with the radiators on, the air becomes very dry. Rather than misting the leaves (which also wets the flowers and can encourage spots), a tray with expanded clay and water works better, keeping the pot above the water level, or you can group several plants together. Good air circulation remains important to prevent rot.

Repotting

Repotting is generally done every 1–2 years, when the bark breaks down and becomes compacted or when the roots come out abundantly from the pot. The best time is after flowering. Gently remove the old medium and cut only the roots that are soft, hollow or blackened, leaving those that are firm and silvery or green.

The Phalaenopsis is a slow-growing plant that needs little fertiliser, but applied regularly during the growing season.

• Use a specific orchid fertiliser, well diluted (usually to half or a quarter of the recommended dose).
• Feed every 2–4 weeks in spring and summer, always on already-moist medium so you don't burn the roots.
• Reduce or stop in autumn and winter, when the plant slows down.

A practical rule popular among growers is "little and often". It's better to dilute heavily and give small, frequent doses than a few concentrated ones. If you prefer a more natural approach, there are liquid organic orchid fertilisers based on plant extracts; in any case the rule of generous dilution applies.

An excess of fertiliser salts leaves whitish deposits on the medium and can damage the roots. Every so often it's useful to water with plain water, without fertiliser, to flush out the build-up.

If you'd like a tailored reminder for doses and timing, Greenkeep's species profile includes a care plan dedicated to the Phalaenopsis that takes the season into account.

When all the flowers have fallen, the plant is not dead: it has simply finished flowering. At this point you have a few choices depending on how the flower stem looks.

If the stem is still green

The Phalaenopsis can rebloom from the same stem. You can cut it just above a visible node in the lower part (usually above the second or third node from the base): a dormant bud can develop into a new flowering branch, though the flowers will often be a little smaller.

If the stem is turning yellow or drying out

When the stem turns yellow, brown or dries out, cut it off at the base with clean scissors. The plant will focus its energy on roots and new leaves, preparing for the next full bloom.

In the meantime, look after the plant

In both cases, after flowering the priority is a strong plant: firm leaves, healthy roots, correct watering and a gradual resumption of feeding. It is during this apparent resting phase that the next flowering is built. If the leaves become soft or turn yellow abnormally, it's worth checking whether there's a watering problem.

The good news is that getting the Phalaenopsis to rebloom doesn't require mysterious tricks, just the right conditions and a little patience. The main trigger is a slight difference in temperature.

The day–night difference

In the wild the autumn drop in night temperature tells the plant it's time to prepare its flowers. You can recreate this at home: for a few weeks in autumn keep the plant somewhere the night temperature drops a few degrees compared with the day, ideally around 13-16 degrees. A lightly heated room or a spot near a window (without icy draughts) is often enough.

The other factors

• Enough light: without adequate light it's unlikely to flower, even with the temperature difference. Dark green leaves signal it needs more indirect light.
• Consistent care: correct watering and regular fertilising in the previous season give the plant the energy to flower.
• Patience: after the trigger, the flower stem can take several weeks to appear and develop. This is normal.

When you see a new stem emerging (distinguishable from a root because it points upwards and has a flatter shape), move the plant back to a stable position and don't shift it around too much.

If you don't know where to start, you can ask Gemma, Greenkeep's assistant, for the reblooming steps adapted to the time of year and the conditions in your home.

Almost all Phalaenopsis problems come down to water. Here are the most common ones.

• Soft, wrinkled leaves: often dehydrated roots or, conversely, roots rotted from too much water. Check the state of the roots before deciding.
• Blackened, mushy roots: rot from overwatering or waterlogging. Repot, cut off the damaged roots with clean scissors and adjust your watering.
• Spots on the leaves: these can come from sunburn or from water sitting in the crown of the plant.
• Yellowed leaves: an old lower leaf turning yellow and dropping is normal; if several leaves yellow at once, suspect incorrect watering.

Pests

The most common are mealybugs and spider mites, encouraged by dry air. For mealybugs, remove the insects by hand with a cotton bud dipped in alcohol and treat with diluted Marseille or potassium soap, or neem oil, going over it again a few days later. Regularly check the underside of the leaves and the hollow at the base. Avoid harsh chemical products: low-impact methods, applied consistently, work well on a plant like this.

Toxicity to animals

The ASPCA classifies the Phalaenopsis orchid as non-toxic to dogs, cats and horses. Even so, it's wise to discourage pets from chewing on it, because any plant can cause stomach upset if eaten.