How to Grow, Harvest, and Eat Yacon

Maddy Harland
Friday, 2nd December 2016

Maddy Harland describes how to grow, harvest and eat this healthy, south American tuber and concludes that yacon is an excellent crop to add to the permaculture garden.

Last February, Charles Dowding gave me some pieces of yacon (Smallanthus sonchifolius) from one of his crowns and advised me to pot them up and plant them outside in late Spring. I have always wanted to grow yacon so I went home and did just that.

About Yacon - why it is good for you

Yacon is South American tuber, much bigger than Oca which I described in my last post, and it has a crunchy, juicy texture. It is also called a ground apple or a ground pear. It is traditionally grown in the Andes and is reported to be very good for you. This is because it contains fructooligosaccharide which is an indigestible polysaccharide made up of fructose. So you get all the benefits of the sweet taste of fructooligosaccharides but none of the calories as they pass through the human digestive tract unmetabolised. Talk about getting your cake and eating it too but without the flab! Not only that, these fructooligosaccharides have a prebiotic effect, so they are used by beneficial bacteria that enhance colon health and aid digestion.

Yacon is a perennial daisy with clusters of yellow flowers (see above) that grows to about four feet (one metre plus). It has furry leaves that are nutritious and can be used like olive leaves to wrap food or cooked like spinach as a green. The leaves contain quantities of protocatechuic, chlorogenic, caffeic, and ferulic acids, and these have prebiotic and antioxidant properties. You can also make the leaves into a tea.

Growing Yacon

Yacon produces crowns and tubers. It is simple to grow. You get hold of a crown early in the year and divide. It is very obvious how to make a division as they have sprouting shoots on the crown. Plant the shoots in a 5-6 inch (13-15cm) pot and place under cover away from frost. Grow the plant on until risk of frost has passed and then plant out in beds mulched with compost or well rotted manure. I planted mine about three feet (one metre) apart.

There doesn't appear to be many pests. High winds may blow down a mature plants (so I made sure I planted them in a sheletered place by the greenhouse) and small slugs can burrow into the tubers like potatoes. I therefore didn't leave them in the soil for too long after the tops had died down. I suspect wireworms would like them too.


Harvesting Yacon

The crowns form over the course of the growing season and can often protrude from the mulch. They are both clusters of budding shoots attached to the tubers and long thin roots that can be propagated.

Below tubers are forming! Wait until the plant has been hit by frost. Apparently, unlike Oca which goes to mush, Yacon likes frost and it increases the sweetness in the tuber. Cut the leaves back to about 4 inches above the crowns - enough to be able to pull on. Place a fork gently around the plant (try not to damage a tuber) and whilst grasping a shoot, lift the plant out of the soil. The crown and tubers should come up in one go. You can always dig for any tubers left behind.


Separate the crowns from the tubers. You can clearly see which is which in the picture below. Place crowns in a sack of damp compost in a frost-free place to plant early next year. From three plants I have ample crowns with shoots to make many new plants in February for my garden and my friends.


Brush the soil off the tubers and place on a windowsill in the sun to dry and sweeten like Oca for up to two weeks. DO NOT SCRUB THE TUBERS! ONCE DAMP THEY CAN GO MOULDY. Then store in a cool, dark place away from the danger of frost.


The exciting thing about Yacon is that it is productive. From three plants we harvested aproximately 33lbs (15kg) of tubers, the largest being over two pounds (915g). Added to this, Charles Dowding tells me that the yields increase year on year as each year I will select the largest crowns and this will increase cropping. So from my first year of three plants yielding over 33lbs (15kg) I have the potential to double this by year three.

Cooking and Eating Yacon

I have eaten Yacon roasted with other root vegetables, kindly cooked for me by the no dig gardener, Steph Hafferty. It has a delicious juicy, crunchy texture but is not over-sweet when cooked. Yacon can also be boiled, cubed and placed in stews and casseroles, grated in a slaw salad, cubed and added to all manner of salads. It can also be juiced or put in a smoothie.

Either treat it like a juicy, crunchy potato or a mild apple. I am thinking that I am really going to like this crop and so are my friends. It has great potential for a no dig, permaculture garden.

Maddy Harland is co-founder and editor of Permaculture Magazine. 

More Useful Information

How to Grow, Store and Eat Oca

Breeding oca for temperate climates

Warm oca salad recipe

Book: Edible Perennial Gardening: Growing Successful Polycultures in Small Spaces

Plants and recipes to bridge the hungry gap

Watch: The micro smallholding