Purple Yacon is one of the most extraordinary plants of the Andes. This spectacular plant is related to the sunflower & grows very similar. It is also called “Pear of the Earth” because it’s tubers have a delicious flavour that resembles a blend of watermelon, apple, & pear. It is very juicy and crisp and can be eaten raw or cooked. Highly recommended, fun to grow for a fall harvest.
Zone 7 – 11
Sunlight – Full sun to partial shade.
Growth rate – Quick.
Drought Tolerance – Poor.
Harvest time – Fall.
Years to Bear Fruit – 1st Year.
Evergreen or Deciduous – Deciduous.
Chill Hours –
In the Andes, yacon matures tubers in six to seven months of growth. Make sure that the plant has eight months in the ground. They continue to grow for a couple of months after onset of flowering. Yacon is very flexible about harvest. It needs about five months in the ground to produce a reasonable yield, but the tubers continue to grow until the plant enters senescence. Harvest yacon around the end of November, or earlier if it was damaged by frost. Harvesting any time after the middle of October should give a reasonable yield.
Unless you treat it like an archaeological dig, you can’t harvest a yacon without breaking a few roots. They are brittle and snap easily when you pull the plant. Work around the base of the plant with a garden spade/fork, inserting it about 15 inches (45 cm) from the stem at a 30 degree angle and levering up. Once worked around the base of the plant, pull it up by the stems. It is a good idea to have a helper, since there can easily be twenty to thirty pounds (9 to 14 kg) of tubers, plus the weight of the soil clinging to the root ball. Remove the larger storage tubers, leaving the small ones attached to the rhizome. Storage tubers and rhizome clumps are washed clean and then left to dry. Though they can be eaten fresh, we recommend that you ignore your yacon tubers for one month after harvest. During this time, they will increase in fructose content, which makes them sweeter. Yacon can taste bland when trying it just after harvest, unless the plants have been exposed to freezing temperatures.
Yacon rhizome is best stored intact, with some small storage tubers still attached. Trim stems back to no more than 2 inches (5 cm) and allow it to dry completely before putting it in storage. Yacon rhizome will mould if it isn’t dry. Keep as close to 38° F (3 C) and 95% humidity as possible. Yacon tubers store really well as long as they are unbroken. They have a respiratory rate similar to potatoes and should last about as long in storage. At 50° F (10 C), these tubers will easily last three or four months and often more if your storage conditions are humid. If you have the ability to cool them down to 35F (2C), they can last up to a year. Broken tubers don’t store as well. The simple solution is to eat those first. Even a badly broken tuber will typically last a couple of weeks before the broken end starts to mould badly. Just cut back to clean flesh and eat the rest of the tuber.
One the most common ways of preserving yacon is to dry it and reduce it to syrup, but it seems like a lot of work, since tubers can be stored for up to a year in the refrigerator.
Yacon forms two types of storage organs: large tubers that you eat and a crown of rhizome that you can cut or break into many propagules in order to start new plants. It is best to break up the crown into pieces of not less than half an ounce (14 g), with at least two growing tips, but five growing tips produce the best results here. The smaller the propagule, the more vulnerable it is to desiccation and decay. There is an art to breaking up a yacon crown, as you want to maximize the amount of protective skin on the propagule and minimize the amount of interior flesh that you expose. Expect to lose a good number of the chunks that you cut.
For storage of propagules over the winter: Don’t cut up the crown until you are getting ready to plant. This only serves to dehydrate the pieces faster. Don’t remove all of the storage tubers from the crown. Leave some of the small ones attached. This greatly improves storage life. Store the crown in dry sand at about 40° F (4 C), or as close to that as you can get, but do not allow the temperature to drop to freezing. If the crown gets wet, it will either sprout or rot, neither of which you want to happen in storage. Crowns can last about six months under the recommended storage conditions.