The question of whether an orchid’s “stem” will grow back after cutting is common, but the answer depends entirely on identifying the correct part of the plant. The most popular houseplant orchid, the Phalaenopsis or “Moth Orchid,” requires specific post-bloom care to flower again. Unlike other plants, cutting the wrong part of this orchid can be fatal, while pruning the correct structure is a necessary step in encouraging a new bloom cycle. Understanding the plant’s anatomy is the first step toward successful reblooming.
Identifying the Flower Spike (What You Are Cutting)
The main plant body of a Phalaenopsis orchid is the crown, which is the true stem, located at the base where the leaves meet. Cutting into this central growth point will prevent any future growth, ultimately killing the plant. The roots emerge from this base, often displaying a thick, silvery-green appearance. The structure the flowers grow on is called the flower spike or inflorescence, which is what most people refer to as the “stem.”
The flower spike is typically thinner, more rigid, and emerges laterally from the true stem, usually from the leaf axle. This spike is characterized by small, triangular bumps along its length, known as nodes. These nodes are dormant growth points protected by a small flap of tissue called a bract. A green flower spike retains the potential for reblooming because these nodes contain meristem cells that can be reactivated.
The Two Approaches to Pruning an Orchid Spike
Pruning the spent flower spike offers two distinct paths for the Phalaenopsis, depending on whether the grower prioritizes an immediate, secondary bloom or a period of rest for stronger future growth. Regardless of the method chosen, it is important to sterilize the cutting tool, such as pruning shears or a razor blade, by wiping it with rubbing alcohol to prevent disease transmission.
One technique is to cut the green spike high to encourage a secondary bloom from an existing node. This involves making a clean cut approximately one-half to one inch above the second or third node, counting up from the base. The goal is to stimulate the dormant bud within that node to develop into a secondary, smaller flower spike, or occasionally a small plantlet called a keiki. While this method yields flowers sooner, the resulting blooms are often smaller, and the process can exhaust the plant.
The alternative approach is to cut the spike low, which promotes plant rest and robust future growth. This technique requires cutting the entire green or yellowing spike back to about one inch above the crown. By removing the spike completely, the orchid redirects energy it would have spent on secondary blooming into producing new leaves and roots. This period of rest allows the plant to build up resources to generate a completely new, primary flower spike, which will be stronger and produce a more impressive display of flowers.
Encouraging Rebloom After Pruning
After the spent flower spike has been cut, the focus shifts to providing the environmental triggers necessary to initiate the next bloom cycle. The primary mechanism for encouraging a new flower spike is a specific change in temperature. Phalaenopsis orchids require a distinct temperature differential between day and night to signal the start of blooming.
To achieve this, the plant should experience a consistent drop in nighttime temperature to between 55°F and 65°F for several weeks. This cool period should maintain a difference of about 5°F to 10°F between day and night temperatures. Once the new flower spike begins to emerge—looking like a small, upward-pointing growth with a rounded tip—the plant can be returned to its normal, warmer environment.
Light and nutrition are important factors during this recovery period. Phalaenopsis orchids thrive in bright, indirect light, such as that provided by an east-facing window or a shaded south or west-facing window. Insufficient light is a common reason orchids fail to rebloom. The plant’s fertilizer regimen should be adjusted to support flower production, often by switching to a high-phosphorus “bloom booster” formula once the new spike is actively forming.