Delosperma

Delosperma is a large and heterogeneous genus of small or medium-sized perennial herbs, shrublets and shrubs that spread decumbently or form clumps, rarely scramble.

Rootstocks are sometimes tuberous and some species have roots with multiple small tubers or taproots. The stems are sometimes reddish. Old stems may have bark that peels.

The leaves are opposite, sessile, slightly fused basally or free and succulent. Most species have pointed leaves, triangular in cross-section or cylindrical, sometimes something inbetween, the upper surface sometimes concave. Glistening water storage cells, known as bladder cells, are visible on the leaf surfaces of several Delosperma species.

Delosperma flowers grow solitary or in groups of three on pedicels of varying length. They have an unmistakable daisy shape, one or more whorls of narrow petals around the flower centre. The flower centre holds four to six stigmas among and below the spreading or cone-shaped cluster of stamens, often a cone of staminodes. The anthers at the stamen tips are often yellow. Five nectar glands lurk below, close to the ovary. Nectar glands are only for visitor food production.

Without pollinators no seeds will be formed in many flower ovaries, causing survival problems for their species. To deal with this, at least some plants need to bear nectar incentives, show colour and exude fragrance. Then other species, deprived of these beneficial attributes, can capitalise on the qualities of their neighbours, as pollinators are often duped, working without reward.

The fruit capsules have four to six locules, the seed-bearing compartments covered by valves. Once the valves open the seeds are there to be seen. The generic name, Delosperma, is derived from the Greek words delos meaning visible and sperma meaning seed. This visibility is due to the absence of covering membranes over the locules of the capsules, typically found in some Aizoaceae genera. Such openly stored seeds are easily washed out by rain.

The genus comprises about 163 species, occurring in a continuous expanse from the Cape Peninsula through eastern Africa to Arabia, as well as on Madagascar and Reunion. Each species occupies only a restricted part of this huge region.

The plants are often hardy, the blooming seasons often long. These features make the plants useful in soil stabilisation and as decorative horticultural items. Many Delosperma plants are easy to cultivate. No surprise that several of the species are favoured by gardeners, also in North America, Australia and further afield.

The Delosperma lavisiae plant in picture was found flowering in open Drakensberg grassland during January (Leistner, (Ed.), 2000; Smith, et al, 1998; Wikipedia).