Senecio herreianus
| Light | Bright, indirect light; a few hours of gentle direct sun suit it well |
|---|---|
| Water | Water thoroughly, then let the mix dry out before watering again; reduce in winter |
| Soil | Free-draining, gritty succulent mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 10–11 |
| Propagation | Stem cuttings (very easy); also layering and seed |
| Toxicity | Considered mildly toxic to cats and dogs if eaten |
Senecio herreianus is a trailing succulent from arid southern Africa, grown for its strings of plump, ovoid leaves marked with translucent longitudinal stripes. Those little striped beads give it the common names string of watermelons and string of beads, and the fine, faint lines running lengthwise down each leaf are its most reliable field mark against the closely related string of pearls. It is one of the most popular hanging succulents in cultivation and, like many of its relatives, is now often placed in the segregate genus Curio (as Curio herreianus).
Description
Senecio herreianus produces slender, trailing stems that root readily where they touch the soil, forming a dense curtain over the rim of a pot or basket. The leaves are the main attraction: small, firm, egg-shaped to almost spherical beads, usually a little larger and more elongated than those of Senecio rowleyanus, and etched with several fine, darker green to translucent lines running from base to tip — the "watermelon" striping.
Each leaf carries a small translucent window (a leaf epidermal "window"), an adaptation that lets light reach the photosynthetic tissue inside while the plump shape limits water loss. In good conditions the trailing stems can grow well over a metre long. Small brush-like flower heads appear on short stalks, typically off-white and lightly fragrant, opening mainly from spring to autumn.
Distribution and habitat
The species is native to the dry country of southern Africa, where it grows in the semi-arid regions of Namibia and South Africa. In habitat it scrambles among rocks and low shrubs, its stems creeping across gritty, fast-draining ground and often sheltering in the light shade of taller vegetation, which protects the beads from the harshest sun.
Cultivation
Senecio herreianus is an easygoing plant, and most losses come from a heavy, water-retaining mix rather than neglect. Grow it in a very free-draining, gritty mix in a pot or hanging basket with good drainage, and give it bright light — a few hours of gentle direct sun bring out the fullest, most well-spaced beads, while too much shade causes thin, stretched growth with widely spaced leaves.
Water thoroughly and then let the mix dry out almost completely before watering again; the plump leaves are a built-in reserve, so the plant tolerates a missed watering far better than a soggy pot. Ease off through winter and keep it on the dry side when cool. Being a trailer, it appreciates room to hang; see Watering and Repotting for general technique.
Propagation
Propagation could hardly be simpler. Stem cuttings a few beads long root quickly when laid on or just pressed into a barely moist gritty mix — the nodes along the stem produce roots readily. Many growers simply pin a length of trailing stem down onto the surface of the soil and let it root in place (layering) before separating it. Seed is possible but rarely used, since cuttings are so reliable and much faster. See Propagation — cuttings for a full walkthrough.
Common problems
- Rot — the usual killer, from overwatering or a slow-draining mix; stems go mushy and translucent at the base.
- Shrivelled beads — persistently soft, deflated leaves usually mean underwatering or root loss following rot; check the roots before simply adding water.
- Leggy, sparse growth — too little light stretches the stems and spaces the beads far apart.
- Pests — mealybugs (white fluff tucked among the beads and at the nodes) are the most common; watch also for aphids on new growth and flower stalks.
See also
- Senecio — the genus overview
- Senecio rowleyanus — the similar string of pearls
- Soil and potting mix · Watering · Propagation — cuttings · Repotting · Pests and diseases