Thistle (Creeping) ~ Cirsium arvense.
Description: Up to 120cm tall. Purple flowers 20-40mm
Location: Grass/wasteland, cultivated areas.
Flowering: July to September

Thistle (Marsh) ~ Cirsium palustre.
Description: Up to 150cm. Flowers purple, sometimes white, to 20mm
Location: Boggy ground and grassland
Flowering: June to September

Thistle (Spear Plume) ~ Cirsium vulgare.
Description: Up to 300cm. Flowers purple/pink to 40mm
Location: Wasteland
Flowering: July to September