To tell us more about the fascinating world of euphorbias is Peter Bangayan, to whom I’m yielding my space this week.)
By Peter Bangayan
One does not necessarily need a large space to collect and grow succulent plants. There are a large variety of miniature succulent plants that the collector can grow. Almost all families of succulent plants have their own miniature members and one of them is the plant family Euphorbiaceae, which consists of about 240 genera and about 6,000 species. The genus Euphorbia of the family Euphorbiaceae contains the most number of succulent species.
Almost all of the succulent euphorbias come from Africa and Madagascar. Euphorbias belong to the milkweed family. They exude a milky sap that can be quite poisonous in certain species. Quite a number of the succulent spurges are small growing and many of these come from Madagascar. Particularly notable and easy to grow here in our tropical climate are plants belonging to the decaryi group. These plants have thick succulent stems and have more or less succulent leaves. Plants usually look like small branching bushes that grow close to the ground in the wild and a number of species from this group are quite readily available. The representative of this group, of course, is Euphorbia decaryi and its varieties. One of the most variable species in this group is Euphorbia francoisii and its numerous forms; forms of Euphorbia francoisii can have diamond-shaped or linear leaves, pinkish red or dark green in color. Some collectors even specialize in breeding and collecting forms of Euphorbia francoisii. Euphorbia cylindrifolia with its cylindrical terete leaves, Euphorbia ambovombensis and Euphorbia capsaintmariensis are also some of the plants with very similar growth habits. Some of the varieties in this group such as Euphorbia cylindrifolia var. tubifera and Euphorbia tulearensis form large underground tubers, which can be raised to make them look like miniature bonsai plants.
Of the branching euphorbias, quite a number of species are small, compact-growing plants. Plants such as Euphorbia golisana, the slow-growing Euphorbia mitriformis, Euphorbia dichroa, Euphorbia marsabitiensis usually form small neat mounds of branches. Except for the slower growing kinds these plants pose no problem in culture provided they are given enough sunlight, proper watering, and feeding. A number of the rarer and slower-growing kinds which come from Somalia such as Euphorbia eilensis, Euphorbia mosaica, Euphorbia horwoodii, and Euphorbia columnaris are usually grafted onto sturdier stocks such as Euphorbia canariensis or Euphorbia resinifera to make them grow faster and also to prevent rotting.
Another form of small-branching Euphorbia plants comes from the so-called millii group. Euphorbia millii and its numerous hybrids are a common sight in plant shops, which are usually cultivated for their large and attractive flowering bracts. There is, however, a number of rarer small-growing plant species from Madagascar that have similar growth habits and are compact-growing. Some of these include E. genoudiana, E. rossii, E. sakarahensis, E. pedilanthioides, E. beharensis, E.guilemetii, and E. neobosseri. These plants are very easy to grow and can take liberal watering. Seed grown plants of E. beharensis, E. pedilanthioides, E. sakarahensis and E. neobosseri usually have a tuber-like taproot. They can be raised and the plants trained to look like old bonsai specimens.
The globose euphorbias have always been popular with collectors although a number of species cannot seem to adapt well to our hot and humid climate. Most of these plants resemble globular cacti and are very succulent. Euphorbia valida, E. meloformis, E. obesa, E. symmetrica, Euphorbia suzannae, and E. gymnocalycioides are some of the small-growing globose types of euphorbias. A number of hybrids though seem to do well in our hot and humid tropical climate.
Medusa head types of euphorbias are usually small- growing plants. Most plants originate from South Africa. These plants usually have a short and thick central stem with branches or arms radiating from the stem, hence the common name medusa head. Most of these types of euphorbias have a hard time growing here in our constantly hot and humid climate. They seem to need several degrees differential between nighttime and daytime temperatures to do well and a winter rest period. Some plants belonging to this group are Euphorbia caput-medusae, Euphorbia inermis, Euphorbia decepta, and the more commonly seen Euphorbia pugniformis. Extra care should be taken when watering these plants as they rot easily when over watered while under-watering will cause the roots to dry up.
Another favorite euphorbia growth form is the small caudex-forming euphorbia. These plants have large tuberous taproots or a caudex and have spiny branches growing from the top of the caudex. Euphorbia stellata, Euphorbia groenewaldii, Euphorbia persistens, Euphorbia squarrosa, Euphorbia micrantha, and Euphorbia clavigera are some representatives of this group. The roots of these plants are usually raised when growing them for display and to avoid rot. These plants are easy to take care of and can take more watering than the globose or the medusa head types of euphorbias.
With the limited space in today’s ever growing and crowded city, the succulent plant collector can always go for the miniature plants of the succulent world. Small-growing euphorbias with their many growth forms will most certainly add interest to any succulent collection. Many of these plants, especially those coming from tropical Africa and Madagascar, are easy to grow; just give them a bright sunlit position, a well-drained growing medium, proper watering and feeding and they should grow well for the collector.