 The staminode takes a variety of forms in the different species; while typically a long straight filament extending to the mouth of the corolla, some are longer and extremely hairy, giving the general appearance of an open mouth with a fuzzy tongue protruding and inspiring the common name beardtongue.Most penstemons are deciduous or semi-evergreen perennials, the remainder being shrubs or subshrubs.Heights can range from 10 cm to as much as 3 metres.