When cooler, or under dull conditions, apply fertilizer once every other watering. Pot Phalaenopsis plants in a well-draining mix such as fir bark, tree fern, various types of stone, sphagnum moss, or combinations of these. Adding 30 percent peat moss to fir bark often results in better growth. Potting is usually done every 1-3 years. Mature plants can grow in the same pot until the potting medium starts to decompose, usually in two years.
Root rot occurs if plants remain in a soggy medium.
When mature, a plant may stay in the same pot size for many years, but must have the medium changed. To re-pot, remove all the old medium from the roots. Trim soft, rotted roots, and spread the remaining roots over a handful of medium in the bottom of a new pot. Fill the rest of the pot with medium, working it through the roots. The junction of the roots and the stem is at the top of the medium.