The Christmas Cactus, or Schlumbergera, is a popular houseplant celebrated for its vibrant winter blooms that often coincide with the holiday season. Proper watering during this flowering cycle is directly linked to the health of the plant and the longevity of its spectacular display. Unlike desert cacti, Schlumbergera is an epiphyte, meaning it naturally grows on trees in the humid, tropical forests of Brazil, which requires a distinct approach to hydration. Understanding this need for consistent, yet controlled, moisture is the most important factor for sustaining a robust floral period.
Specific Watering Requirements for Flowering
During blooming, the plant requires more water than its resting period to support flower production. The goal is to keep the soil consistently moist but never waterlogged, which is a common mistake that leads to root issues. Water only when the top inch or two of the potting mix feels dry to the touch, using the finger test instead of a strict calendar schedule. This responds to the plant’s actual needs, which fluctuate based on the environment.
Apply a thorough soaking until water flows freely from the drainage holes. This ensures the entire root ball is saturated, preventing dry pockets. Immediately discard any excess collected in the saucer or cachepot after the water drains. Allowing the roots to sit in standing water, often referred to as “wet feet,” deprives the roots of oxygen and rapidly leads to decay.
Use room-temperature water, as cold water can shock the root system. While many types of water are acceptable, Schlumbergera can be sensitive to high concentrations of minerals or chlorine found in tap water. Monitoring the soil’s moisture level every three to four days helps maintain the slightly moist conditions required to sustain the colorful flowers.
The Role of Humidity and Temperature
The native environment is characterized by high humidity, and replicating this indoors is beneficial during flowering. Dry indoor air, common when central heating is used, increases water loss through transpiration. This means the plant depletes soil water more quickly, requiring more frequent watering.
A preferred humidity range of 50–60% helps reduce the strain on the plant and keeps the blossoms looking fresh longer. To increase local humidity, place the pot on a shallow pebble tray filled with water, ensuring the pot bottom never touches the water. Evaporation from the tray creates a humid microclimate around the foliage.
Temperature also dictates the frequency of watering, as cooler conditions slow down the rate of water evaporation from the soil. While blooming, the plant prefers consistent room temperatures (60°F to 70°F). Avoid placing it near cold drafts or direct heat sources, as sudden temperature shifts and rapid drying negatively impact the flowers. If the ambient temperature is cooler, water less often.
Preventing and Managing Bud Drop
Bud drop is a common sign of stress in Schlumbergera, frequently linked to inconsistent watering. Both excessive drying and overwatering trigger this protective response. Rapid changes in water supply cause the plant to shed buds to conserve resources.
Environmental shock is a primary cause, often occurring when the plant is moved to a location with different temperature or light levels. If buds begin to drop, the first action should be to check the soil moisture using the finger test. If the soil is sodden, stop watering and allow it to dry out slightly before resuming a proper schedule. If the soil is bone dry, a thorough watering may stabilize the plant.
Once the plant aborts buds due to shock, those flowers will not return this season. The best strategy is preventative: maintain a consistent watering routine and avoid sudden relocations once buds form. Stabilizing the environment halts further bud loss.
Transitioning to Post-Bloom Care
Once flowers fade, Schlumbergera enters a brief rest period, requiring an immediate adjustment to its care routine. This marks the end of the high-demand phase, and water needs decrease significantly. Reduce watering frequency immediately, allowing the top half of the soil to dry out completely before watering again.
This reduced schedule, often translating to watering every two to three weeks, prepares the plant for its next growth cycle. Stop all fertilizer applications, as the plant is no longer actively growing or supporting blooms. Lightly deadhead spent flowers by pinching them off to tidy the plant. This transition conserves energy, setting the stage for a healthy return to bloom next year.