Kalanchoe species are succulents. These popular flowering houseplants belong to the Crassulaceae family, which is largely composed of succulent plants. The Kalanchoe genus includes over 100 species, ranging from small, common potted plants like Kalanchoe blossfeldiana to larger varieties like Kalanchoe tomentosa (Panda Plant). The physical and metabolic traits of these plants are entirely focused on surviving in environments with scarce or irregular water availability.
Characteristics That Define a Succulent
Succulent plants are defined by their ability to store water in specialized tissues, a process called succulence. This adaptation allows them to thrive in arid climates or in soils that drain water quickly. The stored water is typically held in the leaves, stems, or roots, giving these parts a thick, fleshy appearance.
Specialized water-storage cells make up the bulk of the fleshy tissue. These cells possess large vacuoles that can hold significant volumes of water, sometimes making up to 95% of the organ’s weight. Other common adaptations include a reduced leaf surface area to minimize evaporation and a waxy outer coating (cuticle) that seals moisture inside the plant. These physiological traits distinguish succulents as highly drought-resistant plants.
Specific Succulent Adaptations of Kalanchoes
Kalanchoe plants demonstrate their succulent classification through their thick, paddle-shaped leaves. Water is stored within the mesophyll cells of these fleshy leaves, allowing the plant to sustain itself through prolonged dry periods.
Kalanchoes also employ a specialized physiological process called Crassulacean Acid Metabolism (CAM photosynthesis). In most plants, stomata open during the day for gas exchange, resulting in significant water loss through transpiration. CAM plants open their stomata only at night when temperatures are cooler and humidity is higher. This allows them to take in carbon dioxide with minimal water loss, confirming a dual adaptation for extreme water conservation.
Practical Care Based on Succulence
Understanding that Kalanchoes are water-storing succulents directly informs their care requirements as houseplants. The most frequent mistake is overwatering, which leads to root rot because the roots are not adapted to constant moisture. The soil must be allowed to dry out completely between waterings to mimic the natural dry-wet cycle of their native habitats.
The ideal growing medium must be highly porous and well-draining, such as a commercially prepared cactus or succulent mix. This gritty mix ensures that excess water rapidly escapes the pot. Kalanchoes require bright, indirect light to support their photosynthetic processes, though intense, direct sun can sometimes scorch the leaves and should be avoided.