Written by Sandra Lennox and Catherine Clulow
We bring you another great contribution from plant-loving folk in Limpopo. With water restrictions underway in SA and there being a stronger need to encourage water-wise gardening and promote indigenous plants, today we share with readers about Aloes. These unique and beautiful plants are sun-loving and hardy and water-wise.
1. Looking for the sun-kissed plant that is Aloe lettyae, Asphodelaceae
This is the grass aloe with spots on both upper and lower leaf surfaces. The plant population dynamics are being studied from a conservation point of view with funding from the Botanical Education Trust.
This rare aloe, grows amongst the spring flowers of the Woodbush Granite Grassland and may be seen while on one of the hour long wild-flower walks during the annual mid-September Spring Festival, led by the Friends of Haenertsburg Grasslands (FRoHG). The rare aloe plants, not in flower, were photographed one cloudy and cool day, a good day for photographs, although without rain on the trail while accompanied by eco-enthusiasts from nearby towns, of different generations, and the dog Pluto, who watched closely or rested while waiting on the trail move along to the next flowering plant. The land had been burnt, several plants were in flower, belying the fact that there had been little rain. This shows that underground storage organs such as bulbs and tubers are an important part of the survival of these grassland species, hence clearing land for example for firebreaks irreparably destroys the integrity of the flora. The grasslands have established over a long period of time. Coincidentally, the CITES convention had started in Gauteng, to discuss the preservation of endangered species such as elephant, pangolin and naturally the rhino. While scientists and policy makers talked, there are those who walked, appreciating the priceless value of the grassland wildflowers. Rare and endangered plants with medicinal value have been listed for the Woodbush Granite Grasslands (Dzerefos et al. 2016). Aloe lettyae is a summer-flowering aloe.
2. Aloe greatheadii var. greatheadii
This is the spotted aloe with spots on upper leaf surfaces. Commonly occurring, it is an important plant for bees as the pollen has a high protein and lipid nutritional content. You can read more about attracting bees into your garden here.
The spotted aloe, or kgopane (Setswana) flowers in winter (June-July) when it is considered to be spectacular. In habit, the plants are stemless, occurring singularly or up to 15 plants, up to 1.7m high. The dark, shiny green leaves present with spotted, elongated markings arranged in bands on the upper (adaxial) surface, while the leaves are light green and unspotted underneath (abaxial surface). The one to three inflorescences are branched. Each raceme presents 30-40 pale pink to bright red flowers. The pollinators are bees and birds. Wind distributes the seeds. The habitat is in grasslands and bushveld biomes, in open woodland and in overgrazed areas, at altitude from 1000 to 1660m. The distribution is the Free State and northern KwaZulu-Natal. Aloe greatheadii is named after Dr J.B. Greathead who collected the type specimen with Dr S. Schönland. The bitter sap is medicinal, used as a treatment for burns, sores and wounds. The young leaves are chopped and boiled to be used as an antiseptic.
In the garden, sow seed in a mix of sand, compost and river sand. Cover with pebbles. Keep in a dry and warm environment. Avoid drying out the growth mixture. Plants are frost and fire tolerant and are used as soil binders on mine dumps.
3. Aloe marlothii A. Berger
This is the very large, single stemmed aloe seen in large stands along the roadside of Polokwane to Tzaneen, interestingly this is unusual as explained further along.
The large, single stemmed Aloe marlothii occurs in bushveld vegetation on rocky ridges from sea level to approximately 1 600m, at warm temperatures with infrequent frost. Commonly known as the mountain aloe, bergalwyn (Afrikaans), inhlaba or umhlaba (Zulu), Aloe marlothii is distributed from the north-western, northern and north-eastern part of southern Africa and is rewarding to cultivate. Aloe (Greek) refers to the product of dried juice from the leaves, Alloeh (Sanskrit) and Allal (Hebrew). The species is attributed to the botanist H.W. Rudolf Marloth These aloes are associated with the African iron age archaeological sites on the Polokwane (formerly Pietersberg) plateau where the distribution is an anomaly in terms of climate and ecology. The dense stands consist of 80 to 100 year old plants. It is thought that plants were introduced as seeds near the Ndebele villages as the spiny leaves were used to prepare hides for dresses, dried leaf ash may be added to snuff, the flower nectar is edible and leaf decoctions may be used as a vermifuge. The succulent Aloe marlothii plants are suited to drought conditions, as water is stored in stems and leaves, though kudu browse the leaves during dry conditions, thorns protect the rough leaf edges from browsing, dried leaf bases defend the stems and the plant height enables escape from browsers while surviving drought.
4. Aloe arborescens Mill.
This is the most commonly cultivated of southern African aloes. The aloe leaf gel heals sunburn as explained further along.
Commonly known as the kranzaloe (Engl.), kranzalwyn (Afr.), ikalene (Xhosa), inhabane or umlabana (Zulu) it occurs on cliffs in mountainous regions, rocky ranges and outcrops and in dense bush. It occurs in summer rainfall regions and has the widest distribution of the southern African aloes, from the Cape to the eastern coast, KZN and northern South Africa, from sea level to higher altitudes. The cliff dwelling form was formerly known as Aloe mirabilis. Aloe arborescens tolerates drought and it is moderately frost resistant. This is one of the most widely cultivated aloes in the world. It is one of the first aloes collected for cultivation from South Africa. The inflorescences are unbranched and flowers emerge during winter (May to July). These are commonly orange, rarely pure yellow or a combination of orange and yellow. The nectar is edible to birds, for example sunbirds and also bees. Aloe arborescens is recommended for herb gardens. A leaf decoction may be used as an antiseptic and for indigestion, it has been used in stock and poultry farming. The leaf powder is considered to have protective properties against storms. Aloe arborescens are useful barrier plants for example as a hedge. In rural areas, remnants indicate fenced enclosures or cattle kraals.
Aloe lettyae highlights the conservation value of the grasslands. Aloe greatheadii is present as a spotted, grass aloe. Aloe marlothii has been introduced for its economic value. Aloe arborescence is widely cultivated and an early subject for gardens having been collected from the wild. All sun-loving aloes are water-wise and flower while introducing colour.
This article was written with assistance from the Friends of Haenertsburg Grasslands, FRoHG and the Tzaneen Eco-club with inspiration from Gariep nursery, Pretoria which specializes in the cultivation of Aloe. The photos were taken by Pat Lennox.
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