This tall, softly spiny perennial thistle has a large purple flower and a grooved, unwinged woolly stem. Leaves are hairless above but downy beneath. Flowers are borne singly from early July to late August and are followed by a typical thistle seed head.
An upland and northern thistle most commonly associated with stream sides, damp verges, moist woodland edges and upland hay meadows. The loss of this last habitat in favour of silage and the over-management of road verges has led to a decline in Melancholy thistle. Prefers slightly acidic soils.
Seed is best sown in late summer or autumn. Can be established in all parts of Britain but thrives best in the damper, cooler conditions of the northern half of the country. Once established regenerates by means of its creeping runners. Can be added to meadow mixtures EM4, EM5 or EM8.