Kalanchoe blossfeldiana (Flaming Katy): Characteristics & Cultivation

Kalanchoe blossfeldiana is a commonly cultivated evergreen house plant of the genus Kalanchoe native to Madagascar. It is known by the English common names flaming Katy, Christmas kalanchoe, florist kalanchoe and Madagascar widow’s-thrill. Growing well outdoors in U.S. Department of Agriculture plant hardiness zones 10 through 12, kalanchoe needs well-draining, light soil. It doesn’t require a lot of fussy care or fertilizing.

Characteristics of Kalanchoe blossfeldiana (Flaming Katy)

  • Appearance: This plant features thick, succulent leaves that are oval or rounded, with a glossy, dark green color. The leaves can grow up to 3 inches long. The plant’s most notable feature is its flowering clusters, which sit above the foliage on thick stems.
  • Flowers: Kalanchoe blossfeldiana produces vibrant, long-lasting flowers in colors ranging from red, pink, yellow, orange, to white. The flowers are small but numerous, forming dense clusters that resemble tiny bouquets. They bloom in response to shorter daylight periods, making them ideal for winter color.
  • Growth Habit: It’s a compact plant, usually growing to about 1 to 1.5 feet in height and width, which makes it suitable for small spaces and as a potted plant.
  • Toxicity: Contains cardiac glycosides, making it toxic if ingested by pets or humans, so care should be taken in homes with children or animals.

Cultivation of Kalanchoe blossfeldiana

  • Light: Requires bright, indirect light but can tolerate some direct sun, especially in the morning or late afternoon. Direct hot sunlight might cause leaf burn. It’s best placed in an east or west-facing window.
  • Water: Water this plant thoroughly but allow the soil to dry out between waterings. Overwatering can lead to root rot. During winter, water less frequently. It’s drought-tolerant due to its succulent nature.
  • Soil: A well-draining cactus or succulent mix is ideal. Adding perlite or coarse sand can enhance drainage.
  • Temperature: Prefers temperatures between 60-75°F (15-24°C). It’s sensitive to cold and should be kept above 40°F (4°C) to avoid damage.
  • Humidity: Flaming Katy isn’t fussy about humidity and does well in the typical household environment.
  • Fertilizer: Feed with a balanced, low-nitrogen fertilizer every 4-6 weeks during the growing season. During the flowering period, a bloom-booster fertilizer can encourage more flowers.
  • Propagation: Can be propagated through stem cuttings or leaf cuttings. For stem cuttings, allow the cut end to callus over for a few days before planting. Leaf cuttings require laying the leaves on soil until new plantlets form.
  • Pruning: After flowering, prune back the flower stalks to encourage bushier growth and possibly a second bloom cycle.
  • Pests: Watch out for mealybugs, scale, and aphids. If pests appear, treat with insecticidal soap or neem oil.
  • Flowering: To encourage blooming:
    • Kalanchoe needs a period of short days (14 hours of darkness for 6 weeks) to set buds. You can cover the plant or move it to a dark place to simulate these conditions.
    • After the short-day treatment, move the plant to a sunny location to trigger flowering.
  • Repotting: Repot every couple of years or when it outgrows its pot, which isn’t often due to its slow growth rate. Use a slightly larger pot with good drainage.

Additional Tips

  • Avoid getting water on the leaves to prevent rot, especially if you live in a humid climate.
  • After blooming, you can either let it rest and rebloom or treat it as a foliage plant until the next flowering season.