Othonna herrei subsp. herrei
Othonna herrei is a rare plant species that originates from Cape Province, Namaqualand, Richtersveld, South Africa. It is predominantly found on the central mountain ranges of the Richtersveld near Stinkfontein and Numies, with a restricted distribution range of about 517 km² and known from only four locations. The altitude range for this plant species is approximately 300 m. Othonna herrei is adapted to the Succulent Karoo habitat, but it is not commonly abundant in any locality. Populations are thinly scattered in remote and inaccessible areas, specifically on very rocky slopes. This species is known to grow primarily on south- and south-east-facing slopes of rocky mountains, often close to or partially under large rocks and boulders. It prefers areas where the substrate is composed of quartz. Due to its preference for sheltered rocky crevices, Othonna herrei is somewhat protected from the impact of trampling, and is not grazed by animals. It is unlikely to become threatened, even if grazing pressure increases. Mature plants produce little new growth, few flowers and little fertile seed, while the younger plants produce the most flowers and seed. However, flowering is still limited compared to other othonna species. In some localities, Othonna herrei is found growing alongside Othonna retrorsa. This plant species is popular in cultivation and is potentially threatened by collectors who remove mature individuals from the wild for sale in the specialist succulent trade.
Othonna herrei is a curious and dwarf succulent shrub bonsai, growing to 10-20(-30) cm tall, with a few erratic and thick forking branches that are covered in knob-like woody tubercles formed from leaf bases. This appearance superficially resembles Cotyledon wallichiana. Despite being one of the most fascinating species, it’s also one of the most difficult to grow successfully. The plant is dormant during summer, and its leaves are irregularly obovate, undulate, fleshy, and deciduous. They grow on short stalks and have a glaucous green color. After the blade falls, the corky leaf base grows into the already mentioned tubercles. Numerous small yellow flowers are produced in short panicled inflorescences, which are 5-10 cm long and have 3 to 5 tiny, delicate yellow flowers (capitula) that are 12-15 mm in diameter. The phyllaries are 6-7, and the ray flowers are 6-8 and broad and yellow. There are about 20 yellow disc flowers. The blooming season is in summer and often continues later. The stem is short, thick, and caudiciform, with branches covered in smooth cork-like, initially yellow, later dark-brown bark that is about 7-8 cm long and 1.5-3 cm in diameter at the base. The stem bears the prominent and brown remains of leaves bases as persistent, gnarled or knotted tubercles. In habitat, the older plants have heavily blackened trunks in comparison with the brownish gold appearance of the younger plants.
Othonna herrei goes dormant in the summer months and requires watering starting in October, once new leaves begin to form. In April, the leaves begin to yellow and drop off, so it’s best to keep the plant quite dry through the summer. To maintain a compact habit, it’s crucial to cultivate Othonna herrei in the nursery as close to natural conditions as possible, and grow them under harsh conditions.
Othonna herrei prefers a spot with partial sunlight, so its leaves don’t get roasted by the sun’s direct rays. These plants like warm weather, but not scorching temperatures, so make sure the thermometer never drops below 10 °C. When spring and fall come around, give them a good watering, as those are the seasons when they grow and bloom the most. In the summer, they take a break and go into hibernation, so don’t water them too much. Use a soil that’s well-draining and not too nutritious, like a standard succulent soil or a mix of peat and sand/light gravel. And don’t forget to fertilize them once every two weeks in the spring and summer, using half the recommended dose. As for repotting, it all depends on the species.
The most recommended propagation tecnique for Othonna herrei is sowing. Leaf cuttings are in fact widely used for Othonna species but the plantlets obtained reproduced using such method are more prone to become unable to form the caudex, which is the main attractive feature of this species. Sow your seeds in a sandy, well-drained, airy substrate, maintaining it moist until the germination occurs.
This plant is known for its ability to produce new leaves and stems from its woody base, even after being severely pruned or damaged. Despite its popularity among succulent enthusiasts, Othonna herrei is considered a threatened species in the wild due to habitat loss and over-collection for the horticultural trade.
Official Web Site:
Read our advice