This sweetly scented shrublet is a real gem which not only copes with a variety of soiltypes and conditions, but also provides a magical splash of colour from spring to summer.
Agathosma imbricata is a resprouting shrublet with dense, erect branchlets. It grows up to 1 m. The alternate, rounded to oval leaves are 1.5–7 mm longand concave above with fine hairs on margins.The tips of the branchlets bear clusters of white, pink or purple flowers with petals 4–7.5 mm long and with narrow, spoon-shaped, hairy staminodes. The petals have a slender claw (basal part) twice the size of the blade.
||Agathosma imbricata flowers
The ovary and fruits are 3-segmented.
The flowering period is from August to February.
Agathosma imbricata is not threatened and has a status of Least Concern (LC).
Distribution and habitat
The sand buchu is common in parts of the southwestern and southern Western Cape from Saldanha Bay to Mossel Bay. It is found growing on limestone, granite or sandy well-drained or seasonally damp slopes and flats.
Derivation of name and historical aspects
The genus name Agathosma is derived from Greek agathos, which means good and osme, which refers to fragrance. This is meant to indicate the distinctive fragrance so typical of the genus. Oil glands present on the leaves and fruit normally release an aromatic fragrance when crushed.
The specificepithet, imbricata, refers to the leafarrangement and in Latin means overlapping in regular order like tiles.
At present 150 species of Agathosma are known. Most of them are confined to the Western Cape.
As with many buchu species, the sand buchu is abuzz with bees during flowering. They can be observed covering large parts of the plant as they hop from one flower to the next. It is possible that they do assist with pollination.
||Bee visiting Agathosma imbricata
Uses and cultural aspects
No cultural or medicinal uses have been recorded. Planted amongst other fynbos species, the sandbuchu is a gem during the hotter parts of the year. It also makes a nice pot plant.
Growing Agathosma imbricata
Sow the seed of the sand buchu during autumn. Use a medium which is light and has good drainage. A mixture consisting of equal parts of sand and compost, or just plain coarse river sand, will suffice.
Cover the seed with a thin layer of bark or sand, and then water. Place the seed tray in a covered area that provides enough good light and ventilation. The medium must never be allowed to dry out completely or be overwatered.
Germination can take between 4 and9 weeks.
The appearance of the first four true leaves indicates that the seedlings are ready for pricking out. The fine roots must be handled with care.
The potted plants are now placed in a shady area for 3–4 weeks to harden them off before placing them in the sun. This will also be a good time to pinch out the growing tips of the seedlings, as this promotes more bushy growth habit. Regularly feed the young seedlings with some balanced nutrient products.
Plants will be ready for transplanting into the garden after 8 to 9 months.
This buchu can also be propagated by vegetative means by taking heel, tip or semi-hardwood cuttings. This is also the quickest way of ensuring a flowering plant.
Take fresh material from the current year's growth. Prepare cuttings of between 25 and 55 mm, remove about a third of the foliage and cut them below the node. The cuttings are then dipped in a rooting hormone and placed in trays with a medium consisting of equal parts of bark and polystyrene.
The cuttings are now placed in a mistunit with heated benches.
It takes 9–11 weeks for roots to develop.
Pot the rooted cuttings into a well-drained mix and then move them to a shady area for 2–4 weeks to harden off. After this, they can be moved into full sun. In the next 7–8 months plants can be planted in the garden.
Agathosma imbricata will thrive in full sun and well-drained soil where it is planted amongst other fynbos species. The ideal time for planting is in the rainy season between autumn and winter.Plants will then have a better chance of establishing themselves in the garden before they have to cope with less water or drought during summer.
Plants can usually tolerate a fair amount of frost once established.
Before planting, it would be best to dig over the soil, add well-rotted compost and a slow-release fertilizer. This also helps to aerate the soil.
Plant the sand buchu with other fynbos plants such as: Coleonema album, Elegia tectorum, Delosperma littorale, Helichrysum dasyanthemum, Lampranthus aureus, L. amabilis, L. amoenus, Jordaaniela dubia, Protea obtusifolia, P. compacta, Leucospermum patersonii, Salvia african-lutea, Perlargonium betulinum, Lobelia valida, Chrysocoma coma-aurea, Crassula dejecta, Geranium incanum and Cotyledon orbiculata.
Planting at intervals of 200–300 mm should provide enough space to encourage growth. This relative dense planting is something preferred by buchus as it helps to retain soil moisture. Provide a good thorough watering during winter. In summer watering should just be moderate, however, do not allow plants to dry out completely. Regular mulching also aids in keeping the roots and soil cool during summer.
If regularly cut back, this resprouter can be maintained in the garden for many years.
References and further reading
- Goldblatt, P & Manning, J. 2000. Cape Plants. A conspectus of the Cape flora of South Africa. Strelitzia 9. National Botanical Institute, Pretoria & Missouri Botanical Garden, Missouri.
- Goldblatt, P & Manning, J. 1996. West Coast. South African Wild Flower Guide 7. Botanical Society of South Africa, Cape Town.
- Gould, M. 1992. The buchus: cultivation and propagation. National Botanical Institute, Cape Town.
- Manning, J. 2007. Field Guide to Fynbos. Struik Nature, Cape Town
- Powrie, F. 1998. Grow South African Plants. A gardener's companion to indigenous plants. National Botanical Institute, Cape Town.
- Raimondo, D et al. 2009. Red list of South African plants. Strelitzia 25. SANBI (South African National Biodiversity Institute), Pretoria.
- Stearn, W. 2002. Stearn's dictionary of plant names for gardeners. Timber Press. Portland, Oregon.
Kirstenbosch National Botanical Garden