Kalanchoe plants are a popular choice for brightening indoor spaces, known for their vibrant, long-lasting flowers. These succulents, with thick, glossy green leaves and cheerful clusters of blooms, add color to any home. However, many gardeners find their Kalanchoe fails to produce these anticipated flowers. This article explores the factors influencing Kalanchoe blooming and provides strategies to encourage blossoms.
Understanding Kalanchoe’s Blooming Cycle
Kalanchoes are “short-day” plants, meaning they require extended periods of uninterrupted darkness to initiate flower bud formation. In their natural habitat, shorter days and longer nights in autumn and winter signal the plant to prepare for its blooming season. This natural cycle results in flowering during late winter to early spring.
Primary Reasons Kalanchoe Fails to Bloom
Insufficient Light Exposure
Kalanchoes need bright, indirect light for healthy growth. Too much light, especially during their dark period, can prevent blooming. Exposure to artificial light at night, even for short durations, disrupts the plant’s internal clock and inhibits flower bud development. Without prolonged darkness, the plant prioritizes vegetative growth over flowering.
Improper Watering
As succulents, Kalanchoes store water in their fleshy leaves, making them sensitive to watering issues. Overwatering leads to root rot, which stresses the plant and diverts energy from flower production. Conversely, severe underwatering causes wilting and overall plant stress, also hindering blooming.
Nutrient Imbalances
The balance of nutrients in the soil impacts a Kalanchoe’s ability to flower. An excess of nitrogen promotes lush green foliage, but often at the expense of blooms. This encourages the plant to focus its energy on leaf production rather than developing flower buds. Phosphorus, however, is a nutrient that supports root development and flower formation.
Unsuitable Temperatures
Kalanchoes thrive within specific temperature ranges. Ideal daytime temperatures are 60-75°F (15-24°C), with cooler nighttime temperatures around 50-65°F (10-18°C) beneficial for bud formation. Temperatures that are consistently too high or too low stress the plant and prevent blooming.
Lack of a Rest Period
After blooming, Kalanchoes benefit from a rest period. During this time, the plant conserves energy and prepares for its next flowering phase. Without this rest, it may lack the energy to initiate new flower buds, remaining in a vegetative state.
Inducing Kalanchoe to Flower
To encourage blooming, mimic natural short-day conditions. Provide 12-14 hours of complete, uninterrupted darkness daily for 6 to 8 weeks. During the day, for the remaining 10-12 hours, expose the plant to bright, indirect light. Achieve darkness by placing the plant in a dark closet, under a light-proof box, or in a room with no artificial light at night.
During this induction period, reduce watering to allow the soil to dry out almost completely between waterings, and refrain from fertilizing. Once flower buds become visible, return the plant to its normal light and care routine.
Ongoing Care for Consistent Blooms
After blooming, prune spent flower stalks back to the second or third leaf node. This encourages new growth and branching, leading to a bushier plant with more bloom sites. Provide bright, indirect sunlight for 6-8 hours daily during the growing season. Water thoroughly when the top 1-2 inches of soil feel dry, allowing excess water to drain to prevent root rot. Fertilize with a balanced, water-soluble fertilizer, diluted to half strength, every 2-4 weeks during active growth (spring and summer). Reduce or stop feeding in fall and winter.