Flowering kalanchoe plants are reasonably low-maintenance houseplants that draw you in at the garden center because of their numerous, cheerful, tiny flowers. Once those blooms have faded, the plant features succulent leaves that are interesting enough to look at while you wait for a fresh flush of flowers. Paying a little bit of attention to kalanchoe care will ensure your plants thrive year-round—and rebloom for you.
I. Appearance and Characteristics
Kalanchoe also written Kalanchöe or Kalanchoë, is a genus of about 125 species of tropical, succulent plants in the stonecrop family Crassulaceae, mainly native to Madagascar and tropical Africa. A Kalanchoe species was one of the first plants to be sent into space, sent on a resupply to the Soviet Salyut 1 space station in 1979. The majority of kalanchoes require around 6–8 hours of sunlight a day; a few cannot tolerate this, and survive with bright, indirect sunlight to bright shade.
Most are shrubs or perennial herbaceous plants, but a few are annual or biennial. The largest, Kalanchoe beharensis from Madagascar, can reach 6 m (20 ft) tall, but most species are less than 1 m (3 ft) tall.
Kalanchoes open their flowers by growing new cells on the inner surface of the petals to force them outwards, and on the outside of the petals to close them. Kalanchoe flowers are divided into 4 sections with 8 stamens. The petals are fused into a tube, in a similar way to some related genera such as Cotyledon.
These plants are food plants for caterpillars of the Red Pierrot butterfly. The butterfly lays its eggs on leaves, and after hatching, caterpillars burrow into the leaves and eat their inside cells.
II. How to Grow and Care
Sunlight
Kalanchoe plants need plenty of sunlight during the day. In their native range, they thrive in a sunny climate with at least 8 hours per day of light. In dimmer homes, an artificial plant light can provide supplemental light. Kalanchoes growing in less sunlight will get leggy as the stems stretch to get more sun, but strong, southern light can burn the tips of the leaves. Turn kalanchoe plants daily to keep excess growth from occurring that can make the plant unbalanced.
Temperature and Humidity
This plant is from a warm region of the world and has no cold hardiness. In the home, it prefers temperatures of at least 60 degrees Fahrenheit (16 C). This cooler temperature will keep the blooms on the plant longer. After the plant has lost its flowers it may be kept in temperatures up to 80 degrees Fahrenheit (27 C). The succulent is a short day plant that needs cooler temperatures and shorter periods of light in the fall to encourage reblooming.
Watering
This hardy plant does well with minimal water, requiring saturation only every few weeks or so (and even less often during the winter months). Let the soil dry out completely in between waterings to help prevent root rot.
Soil
Outdoors, a kalanchoe plant grows best in well-draining, loamy or sandy soil. Indoor plants should be potted in a well-draining porous blend, like a 50% potting soil and 50% cactus mix, or 60% potting soil and 40% perlite.
To ensure proper drainage and avoid an overly moist environment, plant your kalanchoe in a clay pot, which can help wick excess water from soil.
Fertilizing
Like most flowering plants, kalanchoe benefits from fertilizer, though they’s not heavy feeders. Garden-grown plants require only a single light feeding in the spring. Indoor plants should be fed with a well-balanced fertilizer blend once a month during the spring and summer months, but not in winter. If flowering is sparse, switch to a fertilizer that is higher in phosphorus.
Pruning
Pinching back the stems of a kalanchoe plant will help maintain its shape and promote more robust blooming. Trim off any dead flowers to keep the plant looking neat and encourage new growth. This is especially important to do during the plant’s resting period in late winter and early spring.
Propagation
Kalanchoe is very simple to propagate, and doing so is actually beneficial to the plant’s health. As a mature kalanchoe grows, it produces offsets that can be taxing on the mother plant. Instead of allowing them to leech nutrients from the mature plant, you can propagate the offsets (or take stem cuttings) at almost any time. Here’s how:
- Cut a segment of stem several inches long from a mature plant using a sharp clean knife or clippers. If using an offset, remove it at the joint where it connects to the parent plant.
- Allow the cutting to dry out for a few days, or until the end appears to have healed shut and calloused over.
- Dip the calloused ends of the cutting in a rooting hormone.
- Plant the cutting in soil consisted of the same mixture used to grow the mother plant.
- Place the newly planted cutting in bright indirect light, but do not water it; the stem should take root within a month, at which point you can care for it as you would a mature kalanchoe plant.
Potting and Repotting
Unlike plants that prefer to be pot-bound, kalanchoe plants actually thrive best if repotted rather frequently. For best results, repot your kalanchoe annually in fall after the plant has bloomed. Doing so will encourage new growth and increase the plant’s fullness. Increase the container size to one size larger each time you repot.
Make sure to use a well-draining pot. Clay is a good choice because the material is porous and will help keep the soil relatively dry.
Overwintering
In colder climates, you can relocate indoor kalanchoe plants to the outdoors once night time temperatures are above 60°F. Bring them indoors when temperatures begin to dip in late summer or early fall. If your kalanchoe is exposed to temperatures below freezing (32°F) it may die, so a good rule of thumb is to bring it inside when overnight temperatures dip below 55°F.
In USDA hardiness zones 9 through 11, kalanchoe plants can often survive a frost, even if their foliage dies back. In colder climates, however, they won’t survive frost damage.
During the winter, keep your kalanchoe in a place with bright, indirect light, such as a south-facing or west-facing window, during winter. You can use a grow light if needed.
Kalanchoe plants need less water in winter than they do in spring or summer. Allow the soil to dry out fully between waterings.
Reblooming
Although the foliage of kalanchoe plants is interesting even without blooms, the flowers make the most spectacular display. To force the plant to bloom again, you must fool it into believing it has experienced winter. During October and early March, the day lengths are short enough to naturally force flower buds. In other periods, you will have to put the plant in a closet or dim room for most of the day. Bring it out only for morning light and then put it away after a few hours.
The plant needs six weeks of 12 to 14 hours of darkness to form spectacular new flowers. The best temperatures for the formation of flowers are 40-45 F. (4-7 C.) at night and 60 F. (16 C.) during the day.
Pests and Diseases
Kalanchoe plants are very easy to grow, but problems can arise when they are not watered correctly or if they experience temperature extremes.
- Soft, Damaged Blooms and Leaves
Plants that are touched by near-freezing temperatures will often experience damaged leaves or stunted blooms. For best performance, keep these plants at temperatures above 50°F.
- Wilting
Temperatures that are too high can cause leaves to wilt. Ideally, keep these plants below 80°F.
- Drab or Burned Leaves
Proper light exposure is key to good-looking plants. Too little light and the leaves will lose the trademark glossy green. Too much direct sunlight and you can expect burned leaves. Indoor kalanchoes will do best in a location that receives a lot of bright indirect light, but not too much direct sunlight.
- Soft, Fragile Stems
A very common problem with kalanchoe is overwatering or planting in a soil medium that holds water. Excessive water can easily cause root and stem rot with these plants. If you see this problem beginning, withhold water until the plant recovers.
- Failure to Bloom
When a kalanchoe fails to bloom, it is usually because it does not get the lengthy period of winter darkness that allows the plant to reset its bloom cycle. During the winter months, these plants need a six-week period where they experience nighttime darkness lasting a full 14 hours each day. Without this reset period, the plants usually fail to bloom again.
III. Types of Kalanchoe
- Chandelier Plant
Kalanchoe delagoensis has succulent, tubular leaves splotched in maroon or brown. It can grow to 4 feet tall and is sometimes listed as Kalanchoe tubiflora or Bryophyllum tubiflora.
- Felt Bush
Kalanchoe beharensis has fuzzy leaves with a thick white blush. It often develops warty projections on the underside of leaves. Like panda plant, leaves may be tipped with reddish brown. Indoors it can grow to 4 feet tall.
- Florist’s Kalanchoe
Kalanchoe blossfeldiana has succulent leaves with scalloped edges, but the real reason for growing it is brilliantly colored clusters of flowers. The plant needs bright light and long nights to bloom well.
- Panda Plant
Kalanchoe tomentosa is known for its fuzzy, silvery leaves with reddish-brown tips. It is also called pussy ears.
- Mother-of-Thousands
Kalanchoe daigremontiana has plump, toothed leaves that produce tiny plantlets along their edges. These fall off and start new plants, which can grow to 3 feet tall. It is also known as devil’s backbone, good luck plant, and Bryophyllum daigremontianum.
IV. Uses and Benefits
- Ornamental uses
These plants are cultivated as ornamental houseplants and rock or succulent garden plants. They are popular because of their ease of propagation, low water requirements, and wide variety of flower colors typically borne in clusters well above the leaves.
- Medicinal uses
Traditional medicine
In traditional medicine, Kalanchoe species have been used to treat ailments such as infections, rheumatism and inflammation. Kalanchoe extracts also have immunosuppressive effects. Kalanchoe pinnata has been recorded in Trinidad and Tobago as being used as a traditional treatment for hypertension.
A variety of bufadienolide compounds have been isolated from various Kalanchoe species. Five different bufadienolides have been isolated from Kalanchoe daigremontiana. Two of these, daigremontianin and bersaldegenin 1,3,5-orthoacetate, have been shown to have a pronounced sedative effect. They also have the strong positive inotropic effect associated with cardiac glycosides, and with greater doses an increasing effect on the central nervous system.
Bufadienolide compounds isolated from Kalanchoe pinnata include bryophillin A which showed strong anti-tumor promoting activity, and bersaldegenin-3-acetate and bryophillin C which were less active. Bryophillin C also showed insecticidal properties.
