The common sight of a moth orchid, or Phalaenopsis, after its spectacular initial flowering can lead to confusion for new houseplant owners. The long, arching stem that held the blooms often remains green and seemingly alive. This prompts the question of whether the plant can be coaxed into blooming again from the same old structure. The answer, particularly for the widely available Phalaenopsis variety, is a promising yes, offering the potential for a quick secondary display of flowers.
Understanding Orchid Spike Anatomy and Rebloom Potential
The flower stalk of a Phalaenopsis orchid is a specialized structure known as a spike, which is key to its reblooming potential. Along this spike are small, triangular bumps protected by a sheath, called dormant nodes. These nodes contain undeveloped tissue that can be stimulated to produce a new, secondary flower branch. This ability to rebloom from an existing spike is specific to monopodial orchids like the Phalaenopsis.
The plant activates the already-present dormant buds on the old spike instead of expending energy to grow an entirely new flower stalk from its base. Many other popular orchid types, such as Cattleya or Dendrobium, are sympodial and only bloom on new growth. For these varieties, once the flower spike is finished, it will dry up and should be cut down completely, as it holds no potential for future blooms.
Step-by-Step Guide for Pruning Spent Flower Spikes
Once all the flowers on your Phalaenopsis have faded, the first step is to assess the health of the spike itself. If the spike has begun to turn yellow or brown, it is dying and should be removed entirely, as it will not rebloom and may invite disease. For a healthy green spike, there are two primary pruning options, each with a different outcome.
The first option is the “Partial Cut,” which encourages a faster, secondary bloom. Locate the second or third triangular node counting up from the base of the plant. Using a tool sterilized with rubbing alcohol or a flame, make a clean cut about one inch above this chosen node. This action directs the plant’s growth hormones to the dormant bud immediately below the cut.
A new, shorter flower spike will often emerge from this node within a few months, providing a quicker display of flowers. The trade-off for this quick rebloom is that it draws energy from the plant that could be used for root and leaf development, potentially resulting in smaller blooms.
The second option is the “Full Cut,” where the entire spike is removed at the base, cutting it flush with the main stem or leaving a short stub of about one inch. This method signals the orchid to redirect all its energy into growing new leaves and roots, strengthening the plant for a more robust new flower spike in the next blooming cycle. The Full Cut is recommended if the orchid has only a few leaves, appears weak, or if the spike has turned color, prioritizing the plant’s long-term health.
Cultivating Conditions for Future Blooms
Successfully encouraging a new bloom depends on providing the specific environmental cues the Phalaenopsis needs. After a bloom cycle, the plant requires a period of rest and recovery to gather energy. The most common reason orchids fail to rebloom is insufficient light, which is the primary fuel source for flower production.
The plant should be placed in a location that receives bright, indirect sunlight, such as an east or south-facing window with filtered light. Leaves should be a medium, grassy-green color; if they are dark green, the plant is not receiving enough light to flower. During this recovery phase, fertilizing with a balanced orchid fertilizer at quarter or half strength every other or every third watering will provide the necessary nutrients.
The most significant trigger for new flower spike formation is a consistent drop in temperature. Phalaenopsis orchids need a difference of about 10 to 15 degrees Fahrenheit between day and night temperatures to initiate a new spike. Daytime temperatures should remain between 70°F and 80°F, with nighttime temperatures falling to 55°F to 65°F for several weeks. This cool period mimics the plant’s natural habitat and signals that it is time to set a new spike.