Plectranthus rotundifolius
Plectranthus rotundifolius
Safety & Hazards
None known
Cultivation Details
A plant of the moist tropics. It grows best in areas where annual daytime temperatures are within the range 17 - 27°c, but can tolerate 8 - 36°c[1]. Lower night temperatures promote tuber development[2]. It prefers a mean annual rainfall in the range 1,800 - 2,600mm, but tolerates 1,200 - 4,000mm[1]. Plants are adapted to relatively high rainfall - the best yields are obtained in areas with rainfall well distributed through the growing season[2]. When there is too much rain, the tubers tend to branch, which is disliked by consumers because they are then difficult to peel[3]. Requires a sunny position[3, 1]. Prefers a well-drained sandy loam, but can tolerate a range of soils[2, 1]. Tolerant of poorer, dry soils, though yields are lower in such conditions[3]. Yields are low in heavy soils[3]. Prefers a pH in the range 6.5 - 7.5, tolerating 5.5 - 8[1]. Dislikes waterlogged soils[2]. Plants take 5 - 7 months from planting to harvesting the tubers[2]. The tubers are formed on stems that are in contact with the soil - yields from 7 - 15 tonnes per hectare have been recorded[2]. The tubers need to be harvested quickly or they are liable to decay rapidly[2]. Hausa potato is difficult to store. Traditionally the tubers are stored in the ground under a tree where it is cooler than in the open. When stored in this way under hot conditions the special taste of Hausa potato usually lasts for two months only, after which the tubers become bland and are no longer considered a delicacy[3]. Hausa potato is also packed in bags or baskets stuffed with straw, but if these are kept under warm conditions the tubers will soon shrivel and are no longer edible. To keep the tubers longer, people put them in pots sealed with cow dung. The small tubers needed for the next planting season are stored in this way. In cooler conditions, such as in highland regions or in South Africa, storage is easier[3]. There are some named varieties[2].
Propagation
Seed - not normally used for propagation[2]. Cuttings about 10 - 20cm long[2]. They can be difficult to root[2]. Division of sprouting tubers[2]. They are planted about 5 - 8cm deep[2]. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-20. <tropical.theferns.info/viewtropical.php?id=Plectranthus+rotundifolius>
Pollinators
Insects
References
- [1]Ecocrop — http://ecocrop.fao.org/ecocrop/srv/en/home ↩︎Basic information on a wide range of useful plants, plus details of environmental needs where available.
- [2]Vegetables in the Tropics — Tindall. H. D. · MacMillan, Oxford. · 1983 · ISBN 0-333-24268-8 ↩︎An excellent, in-depth look at the main vegetable crops that can be grown in the Tropics, plus many less well-known plants.
- [3]Protabase - Plant Resources of Tropical Africa. — http://www.prota.org ↩︎An excellent on-line database with detailed information on over 3,200 species of useful plants of Africa.
- [4]Plants of the World online — http://powo.science.kew.org/ ↩︎An on-line database giving detailed descriptions of almost 40,000 species of plants (as of 2018), almost 25,000 images and a list of almost 850,000 plant names. A truly excellent resource and still growing.
- [5]Cornucopia II — Facciola. S. · Kampong Publications, California. · 1998 · ISBN 0-9628087-2-5 ↩︎The second edition of an excellent guide to the edible uses of plants, though it does not give any details of cultivation etc.
- [6]Flora Malesiana Series 1 — Various · Nationaal Herbarium Nederiand, Universiteit Leiden branch · http://www.archive.org ↩︎A massive treatment of the plants of the Malaysian Archipelago. Much of it has been made available to download from the Internet
- [7]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.