Yacón

What looks like a sweet potato, contains no starch, and tastes like an apple crossed with watermelon?

Yacón tubers (Wikipedia) CC BY-SA 3.0

It’s called yacón. Yacón (Smallanthus sonchifolius) is a cousin of sunflowers and Jerusalem artichokes, grown in Central and South America for its crisp, fruity tubers. It goes by several other names, including Bolivian sunroot, Peruvian ground apple, and strawberry jicama.

Yacón description

Yacón is a large perennial herb that grows from rhizomes. It can reach eight feet tall under ideal conditions. The leaves are large and furry on top, and the stems are angular and hollow. The bisexual flowers are relatively small and yellow. Dark brown seeds are achenes.

Yacón flower (Michael Hermann) CC BY-SA 3.0

There are two types of underground tubers. The large brown tubers are preferred for eating, while the reddish rhizomes growing at the base of the plant are generally left to propagate. Those brown tubers can weigh more than four pounds!

How to grow yacón

While you can grow yacón from seeds, the plants will mature faster when started from rhizomes or stem cuttings. Unlike potatoes, you cannot start new yacon plants from the tubers.

Yacón grows best in temperatures between 65F and 78°F. Light freezing will kill the aboveground portion of the plant, but the rhizomes will generate new sprouts when things warm up. Heavy freezes will kill the plant, so you may want to grow yours in a large container. Raised beds with frost protection can also be used.

Plant your yacón around the last frost date. Each rhizome should have several sprouts and be free of any rot. Place them two feet apart and cover them with an inch or so of soil. Mulch the area thoroughly. The yacón plant will grow through the mulch.

Young yacón plants (Suedpfalz) CC BY-SA 4.0

They are heavy feeders, so top dressing with aged compost will help your plants get established. These plants grow fast, which makes them lovely patio plants. In six or seven months, after the flowers have appeared and died back, your yacón crop should be ready for harvesting. The soil around the base of the yacón plant may also begin to ‘heave’ when the crop is ready.

As the upper portion of the plants dies back, the tubers in the ground get sweeter, so you may want to harvest over an extended period.  When you dig up your yacon, do not damage the skin. Brush off any dirt and let them dry in the sun before storing. Yacón is often grown alongside agricultural fields to provide quick refreshing snacks to the workers. You can enjoy yours that way, as well!

Yacón pests and diseases

Root-knot nematodes can create galls on the root system, and sunflower caterpillars may feed heavily on the leaves. You can plant sunflowers among your yacón to draw the caterpillars away.

Several Badnaviruses [Isn’t that a great name for a virus group?], such as the yacón necrotic mottle and yucca bacilliform viruses, can infect these plants. Rhizoctonia blight can also become a problem. You can prevent both diseases by installing certified disease-free cuttings or rhizomes. 

According to WebMD, yacón root syrup may help manage diabetes, inflammation, and weight control. You could be the first person in your neighborhood with fresh yacon on demand!