Succulents Other Than Cacti
( Originally Published 1942 )
SUCCULENTS are so important a factor in all desert gardens and are so intimately associated with cacti in literature that it is very essential to have a rather clear understanding as to what kind of plants comprise this group and some of the uses that can be made of them.
The word "succulent" is a descriptive rather than a definitive term. In botanical literature, it is applied to any plant that is fleshy or juicy. Such plants are scattered through many different families. A genus may be composed of both succulent and non-succulent species. Some plants are so close to the dividing line that even botanists have difficulty in agreeing as to which they are.
There is, however, a rather definite list of plants which by common consent have be-come known as "succulents" by those interpreted in cacti and desert gardens. The plants included in this list have not only fleshy leaves or stems, but most of them have the ability to store moisture for their needs during protracted periods of drought.
It is interesting to note that the Annotated List of Succulents Cultivated in Santa Barbara, published by the Garden Tours Committee, and previously quoted, contains about 560 species of succulents other than cacti and only about 387 species of cacti. It is understood that this is not a list of all members of these groups but only of those grown in gardens of that district; but it does give an interesting suggestion as to the comparative membership of the two groups and their popularity.
A very large number of the succulents used in our desert gardens came originally from foreign countries. In the list above quoted, only forty-seven are given as natives of the United States. The fact that so many of these plants come from distant parts of the world adds much to their popularity.
It is hoped that a brief discussion of a few of these very interesting plants with special emphasis on their decorative possibilities will create in the reader the desire for a more intimate acquaintanceship with the group. One of the most valuable sources of information concerning these plants is the Cactus and Succulent Journal, published by the Cactus and Succulent Society of America, 610 West 65th Street, Los Angeles, California. This journal is not only valuable, but it is almost indispensible to the lover of cactus and desert gardens. Much other useful information may be gathered from the catalogues of nurserymen advertising in the Journal.
One of the names very commonly en-countered in discussions and lists of succulents is Mesembryanthemum. This is a genus of plants belonging to the Carpet-weed or Ice-plant Family (Aizoaceae). The name Mesembryanthemum is a combination of two Greek words meaning "midday flower," and was applied to this group because their flowers usually open only in the bright sun-shine and close at night or when the sun is obscured. The following is an interesting description of the genus taken from the Century Dictionary:
They are erect or prostrate fleshy herbs, sometimes slightly woody, with thick fleshy leaves, and showy white, yellow or rose-colored flowers in terminal or axillary clusters. The fruit is a capsule, which is hygroscopic, swelling out and opening in the rain, and so allowing the seeds to escape. The genus embraces some 400 species, reaching by far its greatest development in South Africa, a few species, mostly littoral (growing near the sea-level) , being scattered in the Canaries, the Mediterranean region, Australia, etc."
Some of the species have very attractive flowers, but the great variations in the form and color of their foliage make them especially valuable in the desert garden. In the descriptions of various species, we find such statements as: "Leaves cylindrical, thick, upright, pointed"; "Leaves long-cylindrical, blunt, glaucus, yellow-green"; "Leaves blunt, with protruding keel, grayish-green, dotted"; "Leaves crowded, about 1/3 inch long, papillose, tipped with cluster of bristles"; "Leaves in dense rosettes, very white-glaucus, bearing a coral-like encrustation on their flattened tips"; "Leaves bright green, triangular in cross-section, with a few teeth at edges"; "Leaves very rough, thick, blunt, toothed, purplish grey"; "Leaves much flattened laterally, wider at tip, hatchet-shaped, bluntly toothed"; "Leaves long and narrow, soft, in upright rosettes from apex to stems"; "Leaves short, very thick, smooth, translucent, leaf-pairs united into an egg-shaped body"; "Leaf pairs united into single button-like bodies, with a trans-verse slit; top marked with translucent areas; brownish red"; "Leaves soft wrinkled, forming a mat." These few excerpts from descriptions given in the Annotated List of Plants Cultivated in Santa Barbara, will give the reader some appreciation of the decorative possibilities of plants from this group.
We are all more or less familiar with the Century plant. What the novice does not usually know, however, is that it belongs to the genus Agave, which is from a Greek word meaning admirable. There are fifty-three species of this genus to be found in the Santa Barbara gardens. The Agaves belong to the Amaryllis Family.
A few of the species have trunks several feet in height, but most of them have little or no trunkthe leaves forming rosettes. The leaves vary from green through spotted, margined, striped, and longitudinally banded. The leaves of some of the species become enormous and they have been known to attain a width of twelve inches and a length of over eight feet. The flower stalks of these larger plants are most imposing. Some reach a height of forty feet, bearing on the end a great cluster of yellow flowers. The smaller species are also very attractive with leaves not more than a foot in length on the more diminutive species and their long graceful flower stems bearing golden, yellow, yellowish-green or maroon flowers according to the species. They obligingly produce young plants as offsets from the mother plant. These babies may be trans-planted and the owner soon has all the specimens needed for the garden.
It does not require a vivid imagination to picture the wonderful effects which may be obtained in a desert garden by the discreet use of these remarkable plants which seem to have about them an aura of the desert itself.
There are a few species of the Milkweed Family (Asclepiadąceę) included in the lists of succulents. They are characterized by their milky juice, and by flowers that are "often hairy, ill-smelling, or dull-colored."
Several species of this group are particularly interesting because they have ribs armed with spines which makes them look very much like cacti. Others are useful in the desert garden because of their trailing habit of growth.
The Pineapple Family (Bromeliaceę) is represented among the succulents by only a few species. These species should not be neglected even though few in number as some of them have very beautiful and showy flowers. A number of the flowers in this group are blue--a color not found among the flowers of cacti and rarely found in any of the other groups of succulents. The leaves of some of the species are also brightly colored, and make a distinct contribution to the garden.
We may be quite astonished to find that here, too, is represented that great group of plants known as Compositę and which is generally thought of as being composed of sunflowers, daisies, and thistles. But here, associating with other succulents, are a few plants belonging to that family. It is true that their appearance seems far removed from our common conception of the group, and most of them claim South Africa as their native home. Probably this very strangeness is the cause of their popularity. One of the most common species is the Candle Plant (Kleinia articulata) which is described as "stems jointed like sausage links, glaucus. Leaves deeply cut, arrow-shaped, flat, stalked. Flowers, greenish white, heads without rays." Some are shrubby, others have tuberous roots, and a few are trailing.
The Crassulaceae is a family composed mostly of thick, fleshy-leaved plants that contributes more species to the list of common succulents than any other family of plants except Cactaceae. There are twenty or more genera represented, and, as is to be expected in so large a group, there is a wide variation in the habits of growth and appearance. We cannot do more at this time than call attention to two of the better known genera.
The Stonecrops (Sedum) are mostly low-growing, spreading plants that reproduce readily by offsets or by seed. Many of them are well adapted to use in rockeries or on walls. The genus contains many attractive and bizarre forms that make delightful additions to a garden, and are especially valuable because they are largely hardy and adapt themselves to arid conditions.
The Live-for-evers (Sempervivum) are little, low-growing, spreading plants that are favorites with many people. Unfortunately, they do not withstand arid conditions well, and much care is required to place them so that they may be given sufficient water without over-watering adjacent plants. They spread rapidly by offsets, and many of them make such thick mats that they are widely used for carpet bedding.
The group of plants known as Spurges (Euphorbiaceae) is very extensive, but there are only a very few included in the list of succulents, and those are mostly members of the genus Euphorbia. In fact, the generic name has been used so extensively that it has almost assumed the status of a common name. When ordering plants of this group, it is not sufficient, however, to simply order a Euphorbia. It is very important to be specific and definite in indicating your wants. Otherwise one may receive a Euphorbia which is not a succulent.
A few of the Euphorbias are so cactus-like in their appearance that they will puzzle the amateur when he first makes their acquaintance. Some of them look more like cacti than do some of the cacti themselves. It will help one to remember that most of these plants have milky juice which is not true of cacti except of a very few species. The forms vary from tiny plants that look very much like a pine cone with a tuft of leaves at the top, to trees that are thirty or forty feet in height.