Sweet potato
Ipomoea batatas
Botanical family: Convolvulaceae
Ipomoea batatas, native to Central and South America, is planted from cuttings ('slips') after the last frosts and harvested in autumn before the first cold. Its sweet tubers are eaten cooked, and its young leaves are also edible in some Asian and African culinary traditions.
Full sun
Warm, light, well-drained, rich in organic matter
Regular at the start of growth, more moderate afterwards
Not hardy (freezes at 0 °C, annual cycle in a temperate climate)
Frost-tender in your zone
Role in permaculture
A tropical perennial grown as an annual in a temperate climate, the sweet potato forms a dense ground cover thanks to its long trailing stems that limit evaporation and smother weeds, while producing edible tubers.
Companions
No companion planting is documented for this plant: no recommended neighbour, no neighbour to avoid.
Insects attracted or useful
Seasons & availability
Not hardy and demanding of heat, sweet potato is grown as an annual in a temperate climate: it is not sown but planted as slips, leafy cuttings started in warmth in March and April, after the last frosts, from mid-May to mid-June. The crop is lifted in autumn, from late September to mid-October, before the first cold. Dried for a few hours in the sun, then kept dry, in the dark and between 12 and 16 °C, colder and they rot, the tubers keep from a few weeks to four to six months depending on conditions. Success outdoors depends on a hot summer and is more reliable in mild regions.
Available: January, February, September, October, November, December.
Guidance for the oceanic / temperate climate; it may vary with your region, altitude, exposure and growing method.
Sources
- RHS, « How to Grow Sweet potatoes » (rhs.org.uk/vegetables/sweet-potatoes/grow-your-own)
- La Ferme de Sainte Marthe, « Réussir la culture de la patate douce » (fermedesaintemarthe.com/en/blogs/comment-reussir-la-culture-de/reussir-la-culture-de-la-patate-douce)
Nutritional & medicinal properties
For educational purposes. Not a substitute for medical advice. Effects depend on the form, the dose and personal context.
Precautions & contraindications
The tuber is eaten cooked and kept dry and cool. The kitchen-garden sweet potato (Ipomoea batatas) must not be confused with the ornamental morning glories (other species of the genus Ipomoea, grown for their foliage or flowers), which are not intended for eating. In case of a special medical diet, seek the advice of a health professional.
Species & varieties
The best-known species and varieties in France.
Common varieties
Voices of peoples
Paraphrases attributed to their documented sources. Never an invented quote.
Quechua speakers of the northern Andes and Māori of Aotearoa (New Zealand), a linguistic parallel · Northern Andes (Gulf of Guayaquil region, Ecuador) and Polynesia; a debate over a pre-Columbian transfer
The Polynesian name of the sweet potato, kūmara in Māori, kumala or 'uala elsewhere, closely resembles the Quechua terms kumar and kumara recorded in the Andes. This lexical parallel, like the attested presence of the plant in Polynesia before the Europeans arrived, is documented; several researchers read in it the sign of a pre-Columbian human transfer from South America. The interpretation, though, remains debated: the exact mechanism, direct Andean-Polynesian contact or other routes, is not settled.
Roullier et al. (2013), PNAS, étude génétique sur la diffusion de la patate douce en Océanie ; l'argument lexical relève de travaux linguistiques distincts sur le doublet quechua kumar/kumara ~ polynésien kumara.
The lexical doublet is real and published, but the thesis of a direct contact remains disputed: the genetic study by Roullier et al. (2013) supports a pre-Columbian transfer without itself carrying the linguistic argument, and a natural dispersal was proposed in response (Muñoz-Rodríguez et al., 2018). The transfer is not presented here as certain, nor are 'the Māori' or 'the Quechua speakers' frozen into homogeneous blocks.
Key takeaways
- • Prefers full sun exposure.
- • Ideal soil: warm, light, well-drained, rich in organic matter.