Yacon

Overview

Yacon grows into a tall, leafy plant with clusters of large tubers that taste like a cross between apple and jicama. The sweetness comes mostly from fructooligosaccharides, which the body doesn’t fully digest, so the tubers are low in calories.

History

Yacon was domesticated in the Andes of South America, where it has been grown for centuries.

Growing on Kauaʻi

• Prefers mild temperatures; grows best at cooler, higher elevations on Kauaʻi.
• Needs loose, rich, well-drained soil and steady moisture.

Planting and propagation

• Plant pieces of the knobby crown (not the edible tubers, which won’t sprout), each with a bud or two.
• Space about 2–3 ft apart, 2–3 inches deep.

Care and maintenance

• Mulch well and water in dry spells.
• Cut back leaves as mulch after harvest.

Role in the guild

Yacon fits the herbaceous layer at the sunny edge of a guild, beside comfrey and pigeon pea.

Harvest

Dig carefully after the tops start to die back, usually 6–8 months after planting; tubers are brittle. Save the crown pieces to replant. Tubers get sweeter after a few days in the sun.

Uses

• Food: tubers eaten raw like fruit, in salads, or lightly cooked; syrup can be made from the juice.
• Soil: leaves and stems as mulch.

Problems to watch

• Struggles in hot, humid lowlands.
• Tuber rot in soggy soil.

General guidance for Kauaʻi; conditions vary by site. Check any new plant at plantpono.org before planting.