Some plants are strictly outdoor plants, while others need a more controlled environment indoors. The thick-leaved kalanchoe (pronounced kal-un-KOH-ee) thrives in either both. This succulent, a relative of the jade plant, hails from Madagascar and not only delivers an array of uniquely shaped, beautiful foliage, but bold, brightly colored flowers, too. Chances are, you’ve seen varieties in the grocery store’s floral shop or nurseries, especially around the winter holidays. They’re a popular gift plant due to their ease of care and showy appearance. Choose from more than 100 varieties in the genus Kalanchoe.
Whether you’re planting them indoors or outdoors, place your kalanchoes in a spot where they’ll have access to plenty of sunlight. Too much direct sunlight can burn the leaves, however, so aim for morning over afternoon sun. Like other succulents, the kalanchoe thrives in warmer temperatures and requires little maintenance. Indoors, they love the low humidity levels that result from household heating in the winter.
Overwatering is the worst thing you can do to a kalanchoe -- they rot in soggy soil. For both houseplants and outdoors, water only when the soil is dry to the touch. Test it by sticking a finger into the soil, about two inches down. In most cases, these plants need watering once every other week, a bit more when they’re blooming. If you have potted kalanchoe on a patio or porch, move them to a covered area if there are heavy rains in the forecast. Cut back on watering during the fall.
Use ordinary potting soil with a handful of sand mixed in for indoor plants. Some experts suggest mixing 60% peat moss with 40% perlite. Create a mix of peat moss, compost, and coarse sand for outdoor plants. Whether indoors or out, ensure the soil drains well. Fertilize monthly with a plant food specifically formulated for succulents, but withhold feeding during the fall. In late winter, fertilize both indoor and outdoor plants with a 0-10-0 to encourage blooms. The plant is toxic for pets, so keep that in mind when choosing where to place your kalanchoe.
In its natural surroundings, the kalanchoe blooms throughout most of the year and grows to between eight and 12 inches tall. Houseplants bloom in the later winter with showy flowers that last into the spring months. Outdoor plants require 12 to 14 hours of darkness each day for a full six weeks to form new flowers. From October through early March, the days are sufficiently short enough to force new buds. As the light increases during the warmer months, the blooms decrease.
If you purchase a kalanchoe plant at the nursery or a grocer’s floral shop, it’s probably blooming. As a rule, these blooms last for weeks or months. What you may not know is that growers force these plants to bloom before distributing to shops. Kalanchoes are short-day plants, meaning they form buds only when there are less than 12 hours of daylight each day. Ten hours of light per day is optimal. Force your indoor kalanchoe to bloom by putting it in a closet or dim room most of the day, starting in mid-March. Propagate new plants using cut stems or offsets, the baby plants that form at the base of the plant.
Like most other flowering plants, removing the spent blooms, or deadheading, keeps kalanchoes looking healthy. It also encourages the plant to open more of its buds, creating more flowers. Getting rid of dying flowers allows the plant to concentrate its energies on flowering, rather than on creating more seeds. To deadhead kalanchoe blossfeldiana, for example, pinch off or clip the spent flower at the short stem or pedicel that connects the opened bloom to the plant’s other bud clusters and flowers.
If you prefer bright, vivid colors, you’ll love the kalanchoe’s wide spectrum of flowers. From delicate, white, bell-shaped blooms to flashy, neon-like reds, this plant offers something for every taste. The flowering blossfeldiana, or florist’s kalanchoe, is a prolific bloomer and available in an array of foliage types and flowers. The Queen Lindsay kalanchoe displays elegant, golden-yellow double flowers, while the Queen Jodie kalanchoe blooms with amazing salmon pink clusters of delicate, tiny, blossoms.
Many plants don’t offer much to look at once their flowers have faded. Nothing could be further from the truth for this delightful succulent. The Kalanchoe tomentosa “Chocolate Soldier” plant has fuzzy green leaves that appear to be stitched with brown thread along the edges. If you’re seeking an unusual plant, try the Kalanchoe daigremontiana, or “Mother-of-Thousands,” which reaches a height of up to three feet. Its toothed-edged leaves grow tiny platelets that fall off and create new plants.
The best zones for growing kalanchoe outdoors are warmer ones, primarily 10 and 11, in the deep south and along the southern U.S. coast. In cooler regions, you can move your potted kalanchoe outdoors once the nighttime temperatures reach 55 degrees. In Florida, for example, many gardeners leave their kalanchoes outdoors year-round. They perform best when the temperatures stay above 60 degrees but don’t exceed 85 degrees.
Kalanchoes attract both aphids and spider mites. Just wipe them off with a wet cloth if you observe them crawling around. If the infestation is more wide-scale, choose an organic, eco-friendly pesticide to get rid of the critters. These plants are also prone to leaf spot disease and powdery mildew. Avoid these diseases by keeping the leaves dry and making sure there’s good air circulation around the plant.