Retting

The extraction of bast fibres from the stems of linen, hemp, ramie, nettle and many other fibreplants is accomplished through retting. The strings of fibers in each are glued together and to the outer bark and the inner wood by pectin. During the retting process, the activity of various fungi, bacteria and weathering dissolve the pectin and the fibres can be separated by chemical and/or mechanical means.

Dew retting takes place directly on the field. The stems of plants are harvested, gathered in bundles, stacked and left to the elements. Depending on temperature and weather, this retting can take some weeks.

Water retting is done in large basins filled with water. Soaking in water the pectin is more quickly dissolved. Earlier in Europe and still today in developing countries, plant fibres are retted in rivers and streams which often is the cause for severe water pollution.