For best results, make sure the nettles are thoroughly mixed with lots of different materials - dry, wet, soft and woody - because they can become a bit slimy on their own.

The hound peered through a clump of nettles, and spotted four figures sitting in the center of the quarry on that indispensable prop to good secret dens everywhere, the common milk crate.

The shade at ground level is perfect for rare Asian nettles; on the brighter upper stories, plants that usually cling to windblown cliff faces brave the blustery British breezes.