Euphorbia obesa
| Light | Bright light with some direct sun; a little shade from the harshest afternoon sun |
|---|---|
| Water | Moderate in growth; allow to dry fully between waterings, keep nearly dry in winter |
| Soil | Fast-draining mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 10–11 |
| Propagation | Seed (needs both a male and female plant) |
| Toxicity | Toxic — milky latex irritates skin and eyes (see below) |
Euphorbia obesa is a small, spineless South African succulent that forms a nearly perfect ribbed sphere, earning it the common name baseball plant. Unlike many euphorbias, it is dioecious — carrying male and female flowers on separate plants — and its neat, symmetrical body and subtle skin patterning have made it a long-standing favourite among collectors.
Description
Euphorbia obesa begins life as an almost globular plant and, with age, elongates into a barrel or short cylinder up to around 15–20 cm tall. The firm, spineless body is divided into eight (sometimes more) broad, low ribs, giving a segmented, seamed appearance often compared to a baseball or a small striped melon. The greyish-green skin is banded with faint purplish or reddish crossbands and lines that vary from plant to plant.
The plant is spineless, but the ribs are edged with a fine row of low tubercles bearing the remnants of old flower stalks. Small, cup-like flowers (cyathia) appear along the crown of the ribs; because the species is dioecious, a single plant produces only male or only female flowers, and both sexes are needed to set seed.
Distribution and habitat
Euphorbia obesa is endemic to a restricted area of the Great Karoo in the Eastern Cape of South Africa, where it grows on dry, stony slopes among low scrub. In habitat the plants often sit partly buried and shaded by surrounding vegetation and rock, which protects them from the fiercest sun and helps them ride out long dry spells.
Wild populations have been heavily reduced by over-collection, and the species is protected in South Africa and listed under CITES Appendix II. Fortunately it is easily raised from seed, so nursery-grown plants are widely available, inexpensive and entirely legal to own and trade; wild-collected material should always be avoided.
Cultivation
Euphorbia obesa is an undemanding and rewarding plant, provided it is not overwatered. Grow it in a very free-draining, mostly mineral mix in a snug pot, in bright light with a few hours of gentler sun. Water thoroughly during the warm growing season once the soil has dried out, then let it dry again; through the cool winter months keep it nearly dry to prevent rot, which is the most common cause of loss.
The plant grows slowly and steadily and is happiest with good airflow and a dry, cool winter rest. See Watering and Repotting for general technique. When handling the plant, be mindful of the caustic latex — see Common problems below.
Propagation
Seed is the standard and usually the only practical method. Because E. obesa is dioecious, you need both a male and a female plant flowering together to obtain viable seed; the ripe capsules can eject their seed forcefully, so growers often bag the developing fruits to catch them. Sow onto a warm, mineral surface kept lightly humid, much as for other succulent seed.
The species is naturally solitary and rarely offsets, so vegetative propagation is uncommon. See Propagation — seed for a full walkthrough.
Cultivars
A number of selected and crested forms circulate in cultivation, including monstrose and cristate (fan-shaped) plants, as well as forms selected for stronger banding or a more elongated, cylindrical habit. Crested and monstrose plants are often slower and more susceptible to rot, and are sometimes grown grafted; see Grafting.
Common problems
- Rot — almost always from overwatering, a slow-draining mix, or cold wet conditions in winter; the body softens and discolours from the base or crown.
- Etiolation — too little light causes the neat globe to stretch and lose its symmetry.
- Pests — mealybugs (white fluff, often at the base or roots) and, in dry stagnant air, spider mites are the usual culprits. See Pests and diseases.
- Irritant latex — all euphorbias bleed a milky white latex when cut or bruised. It can badly irritate skin, and is especially dangerous in the eyes; wash off any sap promptly, keep it away from your face, and keep the plant out of reach of children and pets.
See also
- Euphorbia — the genus overview
- Grafting · Soil and potting mix · Watering · Propagation — seed · Pests and diseases