| Cabbages, Porcelain and Hens and Chickens
Undoubtedly the best known and most widely cultivated of the New World Crassulaceae (Crassula family), the approximately 150 species of the genus Echeveria display almost every possible variation on their basic theme of a rosette of succulent leaves. Everyone is familiar with the most common Echeveria, as components of dish gardens or as the low, mat-forming clusters of blue-green rosettes that lurk in the corners of innumerable back and front yards. Along with these everyday plants, however, there are many unusual Echeveria with strange shapes, spectacular colors and odd habits.
Though Mexico, with well over a hundred species, is the center of their distribution, Echeveria range south through Central America and along the edges of the Andes all the way to northwest Argentina; to the north, a lone species, E. strictiflora, has crossed the Rio Grande and extends a short distance into Texas in the Big Bend region.
The rosettes of Echeveria vary from tightly packed with dozens of leaves to loose and strung out along the thickened, succulent stem. Their tubular or bell-shaped, generally yellow, orange or pink flowers organize themselves in various, taxonomically significant arrangements along a floral scape that emerges from the stem at a point below the growing tip of the plant. Depending on the environments in which they occur, the leaves of Echeveria can be rather thin or extremely thick and succulent, well equipped for withstanding long periods of drought. Only a few Echeveria live in what we would think of as deserts. Many grow in the mixed pine/oak forests that form a major ecozone in Mexico , at altitudes from 4000 to 7000 feet. Some grow at much higher elevations, sometimes over two miles high on some of the tallest peaks of Mexico and in the Andes . A number grow in regions of quite high rainfall, in cloud forest or even in tropical montane rain forests where they may live as epiphytes along with orchids and bromeliads. In all these habitats, though, the plants are found in situations of fairly bright light and extremely good drainage. Plants growing in a forested environment won't be growing in the shade of tall trees, but rather in fissures in big boulders or along the edges of cliffs and ridges where they receive good light and instant drainage no matter how much it rains. Conversely, those species that typically live in truly arid surroundings usually grow in somewhat shaded spots, again often amid boulders and cliff faces, where they get protection from the sun and may benefit from runoff patterns when it does rain.
When the rain stops, the outer leaves of Echeveria dry up and form a protective barrier against further desiccation, while the new grow survives within. As further protection against drying out and too much sun, many species have developed a sun-blocking mechanism, either a powdery, often silvery, pink or blue-white bloom, or a change in leaf color from green to a wide range of colors; blue, purple, pink, orange, red or brown, in the best cases resembling antique Chinese porcelain more than living plants. Under conditions of less than ideal light (which easily occurs in windowsill cultivation), however, the leaves will revert to their underlying green, the sign of an unhappy plant.
Most Echeveria make small to medium, fairly rapidly offsetting rosettes with somewhat thickened leaves. Plants in this category include the extremely common, blue-white E. elegans (the hen and chicken plant) and the bright yellow-flowered E. pulidonis. Plants of a similar general appearance, but slower to reproduce, include the brown to almost black leaved E. affinis, E. shaviana, with delicate rosettes of thin, ruffled leaves covered with pink or lavender-blue bloom, andl as rarely encountered species such as E. strictiflora, E. colorata, and the tiny E. bella. The very hardy E. agavoides and the slow-growing, rarely offsetting E. purpusorum are of a generally similar appearance to the others, but with greatly thickened, drought-resistng leaves. Most of the rarely seen South American species share this look as well.
Other species, such as Echeveria setosa, E. pulvinata, and E. leucotricha, with leaves that remain green, have evolved soft, dense coatings of protective bristles and hair. The pink-brown leaved E. gibbosa and its relatives, including E. pallida and E. gigantea, have been crossed to produce many large, colorful, cabbage sized hybrids, some of which, however, cannot withstand much cold. Probably the most beautiful echeverias are the large, slow growing plants in the taxonomically uncertain complex of species including E. subrigida, E. cante, and E. palmeri, all red edged and covered with dense silvery-blue powder, and the glowing red E. dactylifera. Unfortunately, this last group of plants never offsets and can prove fairly tricky in cultivation.
The list of species could go on and on, along with many hybrids, including intergeneric ones with related Mexican Crassulaceae, but most of the species (and hybrids) have very similar needs in cultivation. Echeveria respond to a quick-draining soil somewhat richer in organic matter than most succulents, and most should never dry out completely, even in winter, when watering them every two weeks or so will keep them happy. During active growth in the warmer months, weekly watering is best. They need bright light, but too much sun can scorch them. Too little light, however causes their distinctive colors to mute into plain green. Most Echeveria can withstand cold, even a little frost, but some, such as E. fimbriata or the Central American E. australis, need to be protected from low temperatures.
Echeveria have been popular in cultivation for centuries and probably always will remain so. Some of them are good plants for beginners, while others are difficult to obtain and challenging to grow. The Garden has a good collection of Echeveria and we always have some to sell, with some rare ones offered from time to time.
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