The Cathedral Bells plant (Sinningia speciosa), a tuberous perennial and relative of the African violet, is prized for its large, velvety, trumpet-shaped flowers. Native to the tropical regions of Brazil, its showy blooms can measure up to four inches in diameter. Flowers appear in shades of red, purple, pink, and white, often with contrasting patterns. Successful cultivation requires understanding its specific needs for growing medium, light, temperature, and its natural life cycle, which includes an annual period of rest.
Initial Setup: Soil and Potting Requirements
A successful start depends on using a light, well-draining potting mix that retains moisture. A mixture formulated for African violets is ideal, typically consisting of peat moss, perlite, and vermiculite. This combination provides necessary aeration to prevent tuber rot while offering the slight acidity, between a pH of 6.0 and 6.5, that the plant prefers.
When planting, select a container with excellent drainage holes, about one and a half times the tuber’s diameter. Plant the tuber with the rounded side down and the concave side facing up, as this is where growth points emerge. The tuber should be planted shallowly, with the top edge level with or slightly below the soil surface.
Optimal Growing Environment: Light, Temperature, and Humidity
The Cathedral Bells plant requires bright, indirect light to thrive and produce blooms. Placing the plant in an east or north-facing window provides sufficient light without the intensity of direct midday sun, which can scorch the delicate, hairy foliage. If natural light is limited, supplemental LED grow lights positioned about 12 inches above the leaves for 12 to 14 hours daily will encourage consistent flowering.
Maintaining a consistently warm environment is important for this tropical native, with daytime temperatures ideally between 68°F and 75°F. Nighttime temperatures can be slightly cooler, in the range of 60°F to 65°F, but protect the plant from cold drafts or proximity to heating and air conditioning vents.
High humidity is required, as the plant thrives best at levels between 60% and 70%. To increase ambient moisture, place the pot on a shallow tray filled with pebbles and water, ensuring the pot bottom remains above the water line. Grouping it with other houseplants or using a small room humidifier are effective methods for maintaining the necessary moisture. Low humidity can lead to the flower buds drying out and dropping before they open, indicating the need for immediate adjustment.
Routine Care: Watering and Fertilization
The Cathedral Bells plant prefers consistently moist soil but is highly susceptible to tuber rot if overwatered. Allow the soil to dry slightly, specifically until the top inch feels dry to the touch, before rewatering. The preferred method is bottom watering: place the pot in a saucer of water for about 30 minutes, allowing the soil to absorb moisture through the drainage holes.
Avoid getting water on the velvety leaves and the crown of the plant, as this can encourage fungal diseases like botrytis or crown rot. During the active growing and blooming season, the plant benefits from regular feeding. Apply a balanced, water-soluble liquid fertilizer, such as a 5-5-5 or 10-10-10 formula, every two to four weeks, diluted to half the strength recommended on the product label.
Ensuring Longevity: Propagation and Dormancy
The Cathedral Bells plant enters a period of dormancy after its main blooming cycle, which is a necessary rest for the tuber to store energy. When the foliage begins to yellow and die back, typically in late fall or winter, gradually reduce watering until the leaves fully wither. Once the leaves have died, store the tuber in its pot in a cool, dark location where temperatures remain around 55°F to 60°F. Provide only minimal water to prevent the tuber from completely drying out.
The tuber can be reawakened after a rest period of two to three months by moving the pot back to a warm, bright location and resuming a regular watering schedule. Propagation is achieved through leaf cuttings or by dividing the tuber. For leaf cuttings, insert a healthy, mature leaf cut at the petiole into a moist, well-draining mix to form a new tuber. Tuber division is best done in early spring before new growth begins, ensuring each section has at least one visible growth point.