Othonna capensis
| Light | Bright light to a few hours of direct sun, which brings out the ruby colouring |
|---|---|
| Water | Water when the soil has dried; reduce in winter but never bone-dry for long |
| Soil | Free-draining succulent mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 9b–11 |
| Propagation | Stem cuttings (very easy) |
| Toxicity | Generally considered non-toxic, but best kept away from curious pets |
Othonna capensis is a trailing, mat-forming succulent from South Africa, grown for its slender purple stems strung with small, bean-shaped leaves and its cheerful yellow daisy flowers. In good light the stems and leaves flush a deep ruby-red, a habit that has earned it the affectionate common names ruby necklace, string of rubies and little pickles. It belongs to the daisy family, Asteraceae, rather than to the true cacti, and is one of the easiest trailing succulents to grow. See the Othonna genus page for its relatives.
Description
Othonna capensis produces thin, wiry stems that trail and root as they spread, forming a loose mat or spilling over the rim of a pot. The leaves are small, cylindrical and bean- or pickle-shaped, held along the stems at intervals. In shade the plant is fairly plain — green leaves on green stems — but under bright light both the stems and the leaves take on purple to red tones, and the little bean-leaves can turn almost translucent ruby, which is where the plant earns its keep as an ornamental.
The flowers are typical of the daisy family: small, bright yellow blooms that open on sunny days and close in the evening or in dull weather, borne on slender stalks above the foliage over a long season.
Distribution and habitat
The species is native to South Africa, where it grows in seasonally dry, sunny habitats. It is a tough, adaptable plant in the wild, spreading over rocky and gritty ground and tolerating both heat and lean soils. This background explains its easygoing nature in cultivation, and its liking for strong light and sharp drainage.
Cultivation
Othonna capensis is one of the more forgiving trailing succulents and is well suited to hanging pots and shelf edges where the stems can cascade. Grow it in a free-draining succulent mix and give it as much bright light as you can — a few hours of direct sun is what coaxes out the famous ruby colouring. In too little light the plant stays green and the stems stretch and thin, so a bright windowsill or grow light makes a real difference.
Water when the soil has dried out, then water thoroughly; the plant stores moisture in its leaves and dislikes sitting wet. Unlike many desert succulents it does not want to be kept completely dry for long stretches — if it is severely under-watered the bean leaves shrivel and drop — so aim for a steady, moderate rhythm and ease off in winter. See Watering and Repotting for general technique.
Because trailing stems can grow leggy over time, the occasional trim keeps the plant full, and the trimmings root easily (see below).
Propagation
Propagation is very easy from stem cuttings. Take a length of stem, let the cut end dry for a day or so, and lay or press it onto barely moist succulent mix; the stems root readily from the nodes, and pieces left touching the soil will often root on their own. This is the standard way to fill out a pot or start new plants, and it makes ruby necklace a generous plant to share. It can also be grown from seed, but cuttings are so quick and reliable that seed is rarely bothered with.
Common problems
- Loss of colour / stretching — the most common complaint; without enough light the stems stay green, grow thin and spread apart. More light restores both colour and compactness.
- Rot — from overwatering or a slow-draining mix; stems go mushy and translucent-brown rather than the healthy firm ruby.
- Shrivelled, dropping leaves — usually a sign the plant has been left too dry for too long; resume regular watering.
- Pests — mealybugs (white fluff along the stems and leaf joints) and aphids on fresh growth are the usual visitors. See Pests and diseases.
See also
- Othonna — the genus overview
- Soil and potting mix · Watering · Propagation — cuttings · Repotting · Pests and diseases