Ensure good light levels in winter, as these are essential to encourage flowering. An east- or west-facing window would be ideal. Move to a shadier spot in summer and protect from direct sunshine. Occasionally wipe off the dust from the leaves with a damp cloth, as dust will block light from reaching the foliage.
Phalaenopsis grows best in a warm environment. Provide night temperatures in the range of 16-19°C (61-66°F) and day temperatures between 19-30°C (66-86°F). Avoid draughts and fluctuating temperatures.
Phalaenopsis produces flowers that last about three months (sometimes even longer) at any time of the year. 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.
If a plant is large and healthy but does not produce flowers in a reasonable time, then reduce the temperature by 5°C (8°F) for four weeks, and a flower spike will usually develop.
Watering, humidity and feeding
Water Phalaenopsis regularly throughout the growing season. Reduce watering slightly during the winter. Always keep the foliage dry, taking care not to splash the leaves when watering. Do not let the roots dry out completely, but avoid letting the plant sit in water. Mist the plant lightly in summer.
Feeding can be done regularly in the growing season – almost every time you water – but plants do need the occasional 'flushing out'. So, apply proprietary liquid orchid fertiliser with three waterings, but use only plain water (with no fertiliser) every fourth watering to ensure that any potentially harmful accumulations of salts are leached from the compost. Feed sparingly during the winter months.
For healthy root growth, ideally re-pot every couple of years before the potting mix has started to disintegrate. Re-pot between March and June using coarse free draining specialist orchid compost. Do not re-pot into too large a pot and choose a pot just large enough to contain the roots. Do not try to bury the fleshy white aerial roots that extend above the pot, as they are prone to rotting.