Where is the origin of yacon? A detailed explanation of the main producing regions

Yacon is native to the mid-to-high plateau zone of the Andes Mountains in South America, from north-central Chile to Peru, Ecuador and Bolivia. At present, yacon is produced in Yunnan, Fujian, Guizhou, Shaanxi, Hunan, Hubei and other parts of China, and it has also been introduced and cultivated in countries such as New Zealand and Japan.

The cultivation techniques for yacon are as follows:

1. Land preparation

Choose a plot of neutral or slightly acidic sandy loam with convenient drainage and irrigation, fertile soil, a deep soil layer (about 50 cm or more), and an organic matter content of 15% or more. When preparing the land, the soil should be fine, even and loose, creating deep, loose soil conditions to improve soil permeability, water storage, fertilizer retention and drought resistance, which is beneficial for full root system growth and development and tuberous root expansion. In the year before planting, deeply plow about 30 cm in winter, let the soil sun-bleach, open deep furrows and make beds; make wide beds in plots with good drainage, and make narrow beds or high beds in plots with poor drainage (bed height 35-40 cm, width about 100 cm, furrow width about 40 cm).

2. Planting

Use single-row planting, with a row spacing of about 140 cm and a plant spacing of about 50 cm, and a planting density of 900-950 plants per mu. When applying base fertilizer, open a furrow about 20 cm deep in the center of the bed, evenly scatter a layer of quicklime in the furrow, and then apply the base fertilizer in a concentrated way. Use 1 kg of commercial organic fertilizer and 0.5 kg of plant ash per hole for the base fertilizer. After applying a thin layer of soil over the surface of the base fertilizer, transplant the seedlings and water thoroughly to settle the roots.

3. Fertilizer and water management

Yacon needs less water in the early growth stage. In the middle and late growth stages, as the tuberous roots expand, the water requirement increases sharply, so timely irrigation is needed. Fertilization should be based mainly on base fertilizer, with appropriate topdressing of potassium fertilizer. When the tuberous roots are expanding, in combination with intertillage and earthing up, apply 50 g of potassium sulfate per plant as topdressing, carry out intertillage and weeding in a timely manner, and pay attention to earthing up and ridging; do not leave the expanded roots exposed on the soil surface.

4. Pruning and pinching

When the yacon stem grows to 1 m high, some tiller branches will appear, and excess branches should be removed; overly vigorous plants also need pinching to control excessive aboveground growth and promote tuberous root expansion.

Yacon generally begins to be harvested successively in early December, and the tuberous roots after harvest should be promptly placed in a cool, ventilated place.