Thistle- Swamp (Cirsium muticum)
Swamp Thistle produces vibrant purple to pink flowers and is weakly armed compared to other thistles. As a biennial it reaches flowering stage in year 2 before dying off. It is a active self-seeder though, so the cycle will continue as long as it sets seed. It is best grown in full sun to moderate shade on wet soils.
Sun Exposure - Full, Partial
Soil Moisture - Wet, Medium-Wet
Height - 7 feet
Bloom Time - July, August, September, October
Bloom Color - Purple
Photo courtesy of Prairie Moon.