Geographical Distribution in Africa
Geographical Distribution of Pelargonium in Africa. Source Wikipedia. Updated on 26th March 2019.
General Information and Agronomic Aspects
Pelargonium sidoides is indigenous to South Africa and Lesotho but now also grown commercially in Kenya.
The pelargonium is a tender evergreen perennial, however commercial interests are based on root extracts of this medicinal herb.
Climatic conditions, soil and water management
Pelargoniums like a sunny exposure, but in very hot areas they benefit from partial shade. They grow well in average soil that is well drained. They are very drought resistant.
Propagation and planting
Propagation is from cuttings, sometimes from seeds. Cuttings can be taken any time of the year except for the coldest months. Choose a compact side shoot about 10 cm long and pull off a small "heel". Remove the lower leaves and press into wet sand. Keep protected and damp until rooted. Plant 90 cm apart, as the rose-scented varieties grow very quickly (Margaret Robert's A-Z Herbs).
Medicinal Properties and Uses
Pelargonium sidoides: This herb is most commonly known by the name "Umckaloabo" which originates from the Zulu language and means "heavy cough". It has long been used in South African traditional medicine to treat coughs and respiratory ailments. Tests in Europe show it may be especially useful against sore throats and bronchitis. The 3-year old roots are the plant parts most often used to obtain extracts, although all plant parts contain active agents. Use certified and tested products.
Information on Pests and Diseases
To avoid problems is obtain plants that are insect and disease-free. Diseases are rare on cultivated Pelargonium species. Overwatering can lead to root-rot; to avoid it regulate watering and use soil or a planting medium with good drainage. Never plant in containers that do not have drainage holes.
Mealybugs maybe be a problem for pelargoniums. Usually they do not occur on the above ground parts, but produce large colonies of insects on the roots, especially tuberous roots, that can seriously damage plants. Above ground they are easy to identify as they appear as white cottony masses.
Aphids can become a problem but they can be easily removed by washing with a strong stream of water.
The caterpillar larvae of some moths do damage to pelargoniums, but they are easily controlled with any of the biological sprays or dusts that contain the bacteria Bacillus thuringienesis (Bt) (UCI Arboretum).