Swamp thistle (Cirsium muticum)

Swamp thistle

Swamp thistle (Cirsium muticum) is native to the central and eastern parts of North America. It acts as a host for some species of butterflies and moths, including the threatened swamp metalmark butterfly. This is one of the few thistles planted in gardens, as it is decorative, not invasive, and attracts pollinators.

Scientific classification

Species

Swamp thistle (Cirsium muticum)

Asters bellflowers fanflowers and allies

Instantly identify plants with a snap

Snap a photo for instant plant ID, gaining quick insights on disease prevention, treatment, toxicity, care, uses, and symbolism, etc.

Download the App for Free

Biennial, Perennial

Lifespan

Herb

Plant Type

Summer, Fall

Bloom Time

91 cm to 2.5 m

Plant Height

Green

Stem Color

Deciduous

Leaf type

20 - 35 ℃

Ideal Temperature

Summer, Fall

Growth Season

Images of Swamp thistle

Culture

Symbolism

Strength, Protection, Hex Breaking

Get quick plant knowledge with a snap

Snap a photo for instant plant identification and learn about its name, symbolism, interesting facts, uses, and more.

Download the App for Free

Quickly Identify Swamp thistle

2-8 feet (60-244 cm) tall, branching stems

Purple to pink flowers with spineless bracts

Leaves up to 10 inches (25 cm) long with wooly white underside

Sparse branching, grooved green stem 2-3 feet (60-90 cm) tall

Dark brown achene fruit with feathery pappus for wind dispersal

Identify plants with a snap

Instantly identify plants with AI: Snap a photo, and get accurate results within seconds.

Download the App for Free

Care Guide for Swamp thistle

Every week

Water

Full sun

Sunlight

20 - 35 ℃

Ideal Temperature

Water: Swamp thistle thrives in moist soil, preferring consistently damp conditions and tolerating waterlogged environments. Weekly watering is recommended to mimic its natural habitat. Typically grown outdoors, it suits rain gardens well. As a herbaceous perennial, swamp thistle needs adequate water during its growing season.

Fertilize: Fertilize swamp thistle in spring with balanced or high nitrogen fertilizer for lush growth, applying quarterly as directed. Benefits include strong stems and better flowering. Maintain damp soil and avoid over-fertilization to prevent root burn. Use slow-release fertilizers for sustained nutrition, adjusting frequency post-bloom.

Pruning: The herbaceous plant swamp thistle thrives with strategic pruning, best performed from early to late spring. Trim previous growth to stimulate new shoots and regularly deadhead to control seed spread and enhance appearance. This practice supports healthier foliage and prevents overcrowding, ensuring a thriving environment.

Propagation: For successful propagation of swamp thistle, use high-quality seeds and surface sow them, as light aids germination. Keep the soil moist and well-draining, avoiding waterlogging. Maintain a protected environment like a cold frame or greenhouse for stability and to shield from disturbances.

Get tips and tricks for your plants.

Keep your plants happy and healthy with our guide to watering, lighting, feeding and more.

Download the App for Free

Images of Swamp thistle

Culture

Quickly Identify Swamp thistle

Care Guide for Swamp thistle

PEOPLE ALSO ASK