Smallanthus sonchifolius (syn. Polymnia sonchifolia) YACON

Yacon Asteraceae

A vigorous, tuberous perennial from the eastern Andes of Colombia, Ecuador, Peru and Bolivia, forming an impressive clump of large, triangular, softly hairy leaves on stout stems to around 1.5–2m. In late summer and autumn it produces small, yellow, sunflower-like flowerheads. Now generally treated botanically as Smallanthus sonchifolius, Polymnia sonchifolia remains a useful and widely encountered name. 

Edible & ethnobotanical: Yacón has been cultivated in the Andes for centuries and was an important traditional food of Andean peoples. Its large, juicy storage roots are the principal edible part, with a crisp texture and refreshing, mildly sweet flavour reminiscent of apple or water chestnut. They are traditionally eaten raw, but may also be cooked, dried or processed into juice and syrup. The roots are unusual among root crops in storing much of their carbohydrate as fructooligosaccharides (FOS) and related fructans rather than starch, giving them their characteristic sweetness. Freshly harvested roots were traditionally exposed to sunlight for several days, which increases their sweetness. The leaves have also been eaten and used traditionally as a tea, although the roots are by far the more important food crop. 

Grow in a fertile, moisture-retentive but well-drained soil in full sun, with shelter from strong winds. Plant out after the last frost and allow a long growing season for the best crop of storage roots. In Britain it is best treated as a tender perennial or annual crop, lifting the rhizomes before severe frost and storing them frost-free for replanting the following spring. 

Flowering: August–October
Hardiness: H2; protect from frost
Height: 1.5–2m
Spread: 0.5–1m

Please note: depending on the time of year, some plants may be cut back before dispatch. This is normal horticultural practice and helps ensure plants arrive in good condition and establish strongly after planting.