Sterilize a pair of shears, soaking the blades in a container with 1 part bleach and 9 parts water for 20 minutes.
Prune the flower stalk back to the base of the plant if the foliage is less than 6 inches long and 4 inches wide. Fully developed leaves on a mature plant are 6 to 12 inches long. Phalaenopsis orchids with smaller leaves need to use their energy to grow vegetation before blooming again.
Trim the flower stalk on mature plants. Cut at a 45-degree angle at the halfway point between two nodes. If the node below the cut swells a few days later, a new series of flowers is on its way.