Clive Stace describes this plant as having the following characteristics:[1]: 564
Upright, to 40 centimetres (16 in); softly hairy, with hairs at more-or-less right-angles to the stem.
Flowers grey-blue, 3–5 millimetres (1⁄8–13⁄64 in) across, saucer shaped in profile; sepal tube with hooked hairs; April–October.[2]: 208
Mature fruit dark brown, shiny.
Mature calyx on spreading stalks longer than sepal tube; calyx teeth conceal the ripe fruit.
Basal leaves stalked, in a rosette; upper leaves not stalked.
Generally found on open, well drained ground; common throughout the British Isles.
^Stace, Clive (2011). New Flora of the British Isles (Third ed.). cambridge, U.K.: Cambridge University Press. ISBN9780521707725.
^Blamey, M.; Fitter, R.; Fitter, A (2003). Wild flowers of Britain and Ireland: The Complete Guide to the British and Irish Flora. London: A & C Black. ISBN978-1408179505.