Most of this genus are tall herbs, starting with a rosette of hairy, grey leaves, continuing up the flowers stems, which are topped with a dense spike of flowers, usually yellow.

Verbascum delphicum is a rare mullein from Greece, with wonderful rosettes of felted leaves, so densely hairy that they appear to be pure silver. Above the leaves rises the tall flowering stem, each branch packed with bright yellow, orange-centred flowers.