Kalanchoe

Types of kalanchoe

• Florist kalanchoe (K. blossfeldiana). The one sold in flower, with scalloped leaves and dense clusters of red, pink, salmon or yellow flowers that last for weeks. It stays compact, usually 6–18 inches tall.
• Plantlet makers. These were once a separate genus, Bryophyllum. Mother of thousands (K. daigremontiana) and mother of millions (K. delagoensis) grow tiny plantlets along their leaf edges that drop off and root in almost anything, including your other pots. Mother of millions has become invasive in some parts of the world, so keep it contained.
• Fuzzy kalanchoes. Panda plant (K. tomentosa) has soft leaves covered in gray-white fuzz, with chocolate-brown spots at the edges; it’s slower to propagate than most succulents. Velvet-leaf kalanchoe (K. beharensis) is a woody shrub, usually 3–5 feet tall in cultivation, with big leaves covered in felt-like hairs.
• Paddle plant (K. thyrsiflora), also called flapjacks. Stacked, paddle-shaped leaves dusted white, with red edges in full sun. Each rosette dies after it flowers, but the offsets around it carry on.

How to make kalanchoe bloom again

Florist kalanchoe only sets flower buds when nights are long. In fall and winter, give it 14 hours of total darkness a day for at least six weeks: a spare room where nobody switches on a lamp, or a closet from late afternoon until morning. Keep it bright by day and cool at night, because temperatures above 80°F (27°C) during the dark period delay the buds. Plants started in early October usually flower by January. Once you can see buds above the leaves, the light no longer matters. Cut off spent flowers to get more.

Kalanchoe care in brief

Bright light: a sunny window indoors (in dim light they get leggy), with some shade from hot afternoon sun if they summer outdoors. Water deeply, then let the soil dry before watering again; soggy soil rots the stems. They’re hardy outdoors only in zones 9–12, so bring pots in before nights drop below 50°F (10°C).

Pets: ASPCA lists kalanchoe as toxic to cats and dogs, with vomiting, diarrhea and, rarely, abnormal heart rhythm as signs.