YACON

fall harvest of sweet and juicy yacon tubers

Yacon, Polymnia sonchifolia, is a perennial plant native to the temperate elevations of the Andes Mountains of South America. Usually eaten raw, the crunchy tubers are sweet and juicy with a melon like flavor. The nutrient rich leaves can be eaten as a green or dried for tea. The wide, six to ten foot tall plant is best treated as an annual in our climate. The yacon tubers are not useful for reproduction. So, yes. Plan on eating all of the many tubers produced by each plant. But, save the bulb-like crown pieces. They are plentiful, not edible and the best reproductive part of the plant.

We have grown yacon in our gardens for the past five or so years. Starting out with only a few crown pieces, we now have hundreds of crown pieces each spring to plant and share. 

Twenty to thirty plants yield more than enough delicious yacon tubers for our family. The tubers can easily be stored and enjoyed from fall to spring. Peel tubers and eat whole like an apple. Peel and slice tubers and add to salads. Grate tubers for slaw. Sliced and dehydrated, the texture of yacon tubers is a lot like dried apples... while the flavor is similar to vanilla!

Start yacon plenty early in order to have mature plants to harvest in the fall. February is best, but early March is not too late.  



Let's begin by looking at the stored crown pieces. 

Just inside the above container is a rinsed bundle of crown pieces from one plant. There are eleven more bundles still buried in the sand.

In the fall, after hard frost, the yacon plant dies back. Time to harvest the crown and tubers. Cut the top of the branches off down to about 12 inches above the ground.  A wide circle is dug around the root area and the plant is carefully lifted from the ground. After harvest, the entire lower ends of a dozen or so yacon plants are stored in a large container. The lower end starts with the 12 inches of stem still attached. At the base of the stem are clusters of crown pieces. Below the crown pieces are tubers. We harvest most of the tubers for immediate eating and drying, but leave some intact. As each lower end of a plant is placed in the container, it is buried in moist sand... until all are placed in the container and buried with sand. The bucket sits inside our closed garage until spring. If, however, we get any lengthy periods of freezing temperatures, the container is moved temporarily to another location where it will be safe from freezing. Meanwhile, throughout the winter, the stored yacon tubers are removed for eating. The tubers stay as fresh, crunchy and delicious in the container as the day they were harvested!

Entire lower end of a harvested yacon plant

In spring it is obvious the crown pieces are ready to grow. The crown pieces look like a big bundle of sprouted tulip bulbs all stuck together!

sprouting crown pieces in spring

Pull apart the large bundle of crown pieces into many small chunks, each chunk showing one or more healthy, sprouting bulb.

Quart sized pots are filled about halfway with soil. Place one chunk of crown pieces into each half filled pot. Then fill the pot with soil to about one inch below the top. Fill the top inch with sand, if available. Water each pot thoroughly and place pots on a tray. Cover entire tray loosely with plastic to hold in moisture.  Place tray on a seed warming mat or in the warmest location in your home:

Once the sprouts appear about two weeks later, remove the plastic cover permanently. Place the plants in a warm, sunny location in your home.

Here they are a month later:

Here is a closer look with daffodils:

When the weather warms up enough outside, maybe the end of April, place the yacon plants outside in a sheltered location like a cold frame or greenhouse. This allows hardening off while continuing to grow. Most years the soil is warm enough to transplant the yacon plants into the ground by late May or early June. The root mass in the pot should be very well developed by now. The yacon plants need fertile soil with good drainage. Yacon need four to six feet between plants. Keep the yacon plants covered with floating row covers as long as possible. They appreciate the extra heat.

Yacon plants from the greenhouse transplanted into a garden outdoors.

Each plant grows into a sizable bush with large, lush, fuzzy leaves. 
The yacon plants below grew to six feet tall and nearly as wide:

Usually, but not always, you will see small, daisy-like yellow flowers growing at the top of mature yacon plants. The flowers look like little sunflowers. Yacon is, in fact, related to sunflower.

Once harvested, rinse the yacon tubers you do not plan to store. Place them in a warm, dry, well lit, indoor location.  Let them sit for a week to ten days. They will wrinkle a little, but this causes them to sweeten up considerably.

These yacon were rinsed and dried. They sat in this sunny window for a week before being sliced and dehydrated.

A jar of dehydrated yacon.

Clean, peel and eat a plump yacon tuber.  So juicy and delicious!

Below is a yacon tuber taken out of storage in March, sliced and placed 
on a bed of kale. The kale was also harvested in March from the garden.  
Yum!       No, we did not grow the lemons.