Panda plant

Identification and origin

Kalanchoe tomentosa belongs to the stonecrop family, Crassulaceae. It is native to east-central Madagascar. The species name tomentosa means “covered with fine hairs,” a reference to the fuzz that coats the entire plant.

It is a semi-woody perennial succulent with an upright habit and a slow growth rate. In cultivation it usually reaches 12 in – 3 ft tall and 2–3 ft wide, and it takes several years to reach full size. The grayish-green stems are densely covered in white fuzz; with age, the base of the stem loses its leaves and turns woody.

The leaves grow in rosettes and are thick, fleshy, oblong, and pointed, 3–4 in long and about 1 in wide. They are pale green but completely covered in a grayish-white felt that is very soft to the touch. Their slightly scalloped edges are marked with chocolate brown spots, which earned the plant its common name.

Indoor plants rarely bloom. When flowering does happen, in spring or summer, a stalk about 18 in tall carries narrow panicles of small tubular flowers ranging from yellowish green to brown or purple.

Several cultivars are widely grown: ‘Chocolate Soldier’, faster growing and clumping, with thinner, longer leaves edged in reddish brown; ‘Cinnamon’, with long, russet leaves that turn almost black in full sun; ‘Teddy Bear’, with rounded chocolate brown leaves; and ‘Panda’.

Light

The panda plant needs bright light for at least six hours a day. Set it right next to a south- or east-facing window, in a spot with good air circulation. It tolerates direct sun, but in very hot climates, shield it from the harshest rays to prevent leaf burn.

A lack of light shows quickly: the stems stretch, become leggy, and the rosettes spread farther apart. If that happens, move the plant closer to the window gradually.

Watering

Let the potting mix dry out between waterings. Push a finger into the mix: as long as it still feels moist, wait. Once it is dry, water moderately, pouring onto the soil rather than into the center of the rosettes, where standing water encourages rot. Always empty the saucer, since the plant should never sit in water.

During its winter rest, water even less often. The leaves act as a gauge: wrinkled or shriveled leaves point to underwatering, while yellow or mushy leaves, like stems that turn soft, point to overwatering. The plant prefers dry air, so there is no need to mist it or raise the humidity.

Potting mix

Use a cactus and succulent mix, or a peat-free, loam-based potting mix lightened with sharp sand or grit. The mix should drain very quickly. Soil pH matters little: the plant adapts to acidic, neutral, or alkaline mixes. A shallow terra cotta pot with drainage holes helps the mix dry out between waterings.

During the growing season, two or three feedings with a balanced liquid fertilizer are enough. Do not fertilize in winter.

Temperature

It grows best between 61–75 °F. It tolerates neither frost nor extreme heat, and it should not be exposed to temperatures below 50 °F. It can spend the summer outdoors, out of the scorching afternoon sun, but bring it inside before the first frost. In the ground it is grown in USDA zones 9a to 11b, where it is used in rock gardens, succulent beds, and borders.

Repotting

Because the plant grows slowly, it rarely needs repotting. Move it up when the roots fill the container: choose a pot only slightly larger, with drainage holes, ideally a shallow terra cotta one, and fill it with fresh, fast-draining succulent mix. Handle the plant gently so you do not damage its fuzzy leaves. Afterward, resume watering according to how dry the mix is, letting it dry out between waterings.

Pruning

No pruning is needed. Simply remove dead leaves from the base of the plant to keep it healthy.

Propagation

The panda plant is a little harder to propagate than many other succulents, but several methods work:

• Leaf cuttings: remove a healthy, whole leaf and lay it on a well-drained succulent mix.
• Stem cuttings: cut off a stem tip with its rosette and insert it into a succulent mix.
• Offsets: separate the small shoots that appear at the base and replant them.
• Seed: can be sown in early spring at 66–70 °F.

In every case, give young plants the same conditions as mature ones: plenty of light, a mix that dries out between waterings, and never any standing water.

Common problems

• Wrinkled or shriveled leaves: the mix has stayed dry for too long.
• Yellow, mushy leaves or stems, root rot: too much water, a mix that is too dense, or a saucer left full.
• Stretched, bare stems: not enough light.
• Scorched patches on the leaves: sun that is too intense, especially in summer.
• Mealybugs, aphids, spider mites: regularly inspect the base of the leaves and the center of the rosettes.
• Powdery mildew or rust: these diseases can appear, especially in stuffy, poorly ventilated conditions; improve air circulation.

The same symptom can have several causes: before acting, always check the moisture of the mix, the amount of light, and the condition of the roots.

Toxicity

All parts of the plant are poisonous if eaten, to people as well as to dogs and cats. They contain bufadienolides, glycosides that act on the heart. Eating the plant causes nausea, vomiting, diarrhea, and lethargy, and more rarely an abnormal heart rhythm. The plant does not cause contact dermatitis. Keep it out of reach of young children and pets, and if any part is swallowed, contact a veterinarian or a poison control center.