repelenThe flax was first stored in flax barns. Then it was threshed or deseeded. For the removal of the bark flax must then be retted. Retting is the process of rotting away the inner stalk, leaving the outer fibers intact. That happened in the river. Also pools, some of which are still called 'Rootven', were used for this purpose. Later, the root process was performed in concrete tanks. In that case the flax was immersed 100 hours in water at 37.8°C. It took 6 to 10 days before the flax was 'cooked', and at last a flax stem was 2 to 3 times a day drawn from the pit to control the process. The removing of the flax from the wells was a very dirty and smelly chore.

This process provided the finest quality linen. The flax had often suffered from flax fever, caused by the butyric acid bacteria released during retting.

Today, the harvest is done mechanically, and the flax is laid flat on the ground where the retting process begins. This is the dissolving of the pectin that binds the fibers together. This is called dew retting: flax laid on the field was at regular times turned to obtain a uniform retting.
In this, probably the oldest method flax was spread during 3 to 6 weeks.
During the turning flax can be threshed.