Cirsium japonicum, commonly known as Japanese thistle, is a biennial or short-lived perennial herb native to grasslands, coastal areas, and open woodlands in Japan, as well as parts of China and Korea. It typically grows to a height of 30-100 cm (12-39 inches) and features spiny, deeply lobed leaves and a stout stem. From summer to early autumn, it produces attractive, fluffy, pink to purple flower heads that are highly attractive to pollinators but can also spread prolifically if not managed. The plant is known for its resilience and can tolerate a range of soil conditions, though it prefers well-drained soils.

Japanese thistle is not commonly cultivated but may be used in wildflower meadows or naturalistic plantings where its aggressive nature can be contained. It requires minimal maintenance once established and can thrive in full sun to part shade. However, gardeners should be cautious as it can become weedy and potentially invasive outside its native range, particularly in areas with similar climates. In some regions, it is considered a noxious weed and its cultivation is discouraged or prohibited.CC BY-SA 4.0