Use a fork to run through the surface of the cucumber, vertically downwards, to obtain a fluted pattern when sliced.
Cut cucumber into thin slices and put into a large bowl, sprinkle with salt and mix well. Leave the cucumber for 10 minutes to absorb the salt then rinse with cold water. Drain off excess liquid in a colander. Return cucumber to the large bowl.
Grate the fresh root ginger. Cut the stem ginger into thin slices.
Combine sugar, vinegar and the two types of ginger together. Add to cucumber slices and mix well.
Decant into a plastic container. Refrigerate overnight or for a few hours before serving.