Crassulaceae is the botanical name of a group of characteristically fleshy plants, often called succulents. These plants are in the Orpine family. Generally, these plants are herbs and shrubs that live in dry, arid areas. Genera belonging to the Crassulaceae family include Crassula, Sedum, Sempervivum, and others. Many plants belonging to the various genera are highly prized for house and garden plants, including stonecrop and hen and chicks.
A person should research the proper growing conditions for plants from the Crassulaceae family because the plants grow in a wide range of environments. Although plants in this family generally prefer dry climates, some of the plants, such as the Crassula ericoides, like plenty of water and sandy soil that lets it drain away quickly. Some of the plants are small when mature, but others may become almost tree-like. Cotyledon orbiculata, or pig's ear flower, often grows to 12 to 24 inches (about 30 to 61 cm), while a common hen and chicks plant, Sempervivum tectorumem, generally is less than 4 inches (10 cm) tall.
Plants in the family have a very wide range of habitat. One of its genera, Sedum, has plants that grow from northern areas, such as Iceland, to southern areas, such as Bolivia and Peru, and many areas in between. Most Sedum plants grow well in rock gardens and are hardy in most sections of the United States and other countries. Although most varieties of hen and chicks are native to northern Africa and parts of Europe, gardeners throughout the world use them for ornamental plantings, especially in rock garden landscaping. These plants are very hardy, and gardeners should check with local nurseries to learn which varieties are hardy in that area.
Gardeners need to know about the plants of the Crassulaceae family that they are growing. Some of the plants, such as Sedum acre, may be toxic to animals or at least cause irritation. The poisonous Sedum rubrotinctum usually causes illness when ingested and sometimes irritation when touched.
Although some of the plants are toxic, herbalists have used others for centuries. In his book, Materia Medica, Discorides, who lived from 40 to 90 AD, advises that Sempervivum leaves crushed into wine eliminate intestinal parasites, such as flukes and worms. Another early herbalist, Pliny the Elder, who lived from 23 to 79 AD, wrote in Naturalis Historiae that he used Sempervivum leaves to treat a large variety of skin conditions, such as burns and ringworm. The Romans used it as a pesticide to protect their crops from caterpillars. In parts of South Africa, native herbalists treat skin conditions, such as abscesses and warts, with Cotyledon orbiculata.
Herbalists need to use caution when recommending any plant from the Crassulaceae family. The genus Kalanchoe contains about 125 species, many of which are common house and garden plants. Many of the species contain plants that have toxins that can negatively affect a person's heart rhythm. Often grazing animals who accidentally ingest the Kalanchoe plants suffer from cardiac poisoning. It is important to keep these plants away from small children and pets.