Plume Thistle Trevor’s Blue Wonder A new, thistle-like plant that’s very similar to the fashionable Cirsium rivulare Atropurpureum, Cirsium rivulare Trevor's Blue Wonder is an average to fast-growing herbaceous perennial with an upright, clump-forming habit. The spiny, grey-green foliage is oblong to lance-shaped, and deeply divided. From June to August, rich purple-magenta, thistle-like flowers are carried on the tall, purple-flushed stems; the flowers are lighter and bluer in colour than Atropurpureum’s, and very attractive to pollinators. Leave the last flowers to seed, as the seeds are good for finches, although there will be some self-sowing. Plume thistle Trevor's Blue Wonder looks very attractive planted with moisture-loving grasses of similar height, such as pennisetums. Site: Tolerates exposure; open, sunny siteSoil: Any moist but well-drained soilPosition: Best in full sunSeason of interest: All summerHardiness: Very hardyHeight: 4’ (1.2m) Spread: 2’ (60cm)