The Kalanchoe blossfeldiana, commonly known as the Florist Kalanchoe or Flaming Katy, is a popular succulent houseplant valued for its vibrant, long-lasting clusters of flowers. Originating from Madagascar, this species has thick, fleshy leaves characteristic of succulents, adapting it to dry conditions. Its appeal lies in the brilliant colors of its blooms, which range from red and orange to pink and yellow, making it a favorite for adding color indoors. Caring for this plant requires understanding its specific light and water needs to ensure successful, repeated flowering.
Setting Up the Proper Habitat
Establishing the correct environment is foundational for the health and blooming potential of the Kalanchoe. The plant thrives in a location that receives bright, indirect sunlight throughout the day. While ample light is needed to flower profusely, harsh, direct midday sun can cause the leaves to scorch. A sunny east-facing window or a slightly shaded spot near a south-facing window provides the ideal balance of brightness.
The correct temperature range helps mimic the plant’s natural subtropical habitat. Kalanchoe plants prefer average indoor temperatures, ideally maintaining 60°F to 85°F during the day. Nighttime temperatures should be slightly cooler, around 50°F to 60°F, which assists in flower bud development. Keep the plant away from sources of cold air, as temperatures below 40°F can severely damage the foliage.
Because the Kalanchoe is a succulent, the potting medium must facilitate rapid water drainage to prevent root moisture. A specialized cactus or succulent potting mix works best. Standard potting soil amended with materials like perlite or coarse sand also provides necessary aeration. The container must have drainage holes, as excess water retention is the most common cause of root rot. Repotting every one to two years with fresh soil supports continued vigorous growth.
Regular Watering and Nutrient Needs
Proper watering involves treating the Kalanchoe like a succulent: deeply but infrequently. The plant stores water in its thick leaves and stems, tolerating dryness better than excess moisture. To determine when to water, allow the top two inches of the soil to dry out completely before applying water again.
When watering, soak the soil thoroughly until water flows out of the drainage holes. Discard any water that collects in the saucer after ten to fifteen minutes to prevent the roots from standing in a saturated environment. During the winter months, when growth slows, significantly reduce the frequency of watering to allow for semi-dormancy.
Kalanchoe plants are not heavy feeders and thrive with minimal fertilization. If you choose to fertilize, do so only during the active growing season (spring through summer). Apply a balanced, water-soluble fertilizer diluted to half strength once a month to support healthy foliage and flower production. Stop fertilization completely during the fall and winter, especially when preparing the plant for re-blooming.
Pruning and General Upkeep
Maintaining the Kalanchoe involves routine removal of spent flowers and occasional shaping. Removing faded blooms, known as deadheading, encourages the plant to direct energy toward new growth rather than seed production. Pinch or snip off the entire flower stalk down to the first set of healthy leaves or a leaf node.
After the main flowering period, lightly prune any long and sparse stems, a condition known as legginess. Cutting these stems back just above a leaf node encourages the plant to branch out, resulting in a more compact form. Always use clean, sharp scissors or shears to make precise cuts, minimizing the risk of introducing disease.
Regularly inspecting the plant for common houseplant pests is an effective part of general upkeep. Kalanchoe can occasionally attract insects like aphids or mealybugs, which congregate on the undersides of leaves or in stem crevices. If small infestations are detected, remove the affected parts immediately and isolate the plant to prevent the spread of pests.
The Process of Re-blooming
The most specific requirement for the Kalanchoe is a controlled period of darkness to initiate the next cycle of blooms. This plant is classified as a short-day plant, requiring extended, uninterrupted darkness to trigger flower bud formation. This requirement must be artificially replicated indoors, as typical household lighting prevents the necessary shift.
To force a re-bloom, subject the plant to a strict schedule of darkness and light for approximately six to eight weeks. This process should begin in early fall (October or November) to achieve blooms during the late winter months. The schedule requires 14 hours of complete and continuous darkness daily, followed by 10 hours of bright light.
Complete darkness is essential, as even a small amount of light can disrupt the process and prevent bud set. Place the plant inside a light-proof closet or cover it with an opaque box every evening and uncover it every morning. During this six-to-eight-week period, watering should be minimal—just enough to keep the leaves from shriveling—and fertilization must be completely withheld. Once the flower buds are clearly visible, stop the controlled light cycle and move the Kalanchoe back to its regular location with bright, indirect light. Gradually increase the watering frequency and resume a light fertilization schedule to support the developing flowers.