DESCRIPTION: This group of annuals, biennials, and perennials are natives in damp meadows in central and southwestern Europe and North America. Most of these plants, however, are weeds. The main kinds that are cultivated are as follows: C. Rivulare atropurpureum is a clump forming perennial that grows 4 feet or more high. Its leaves are narrow and deeply divided and produced mostly at the base. The small, dark crimson flowers resemble little thistles. They grow in small bunches atop long stems in mid-summer. C. Diacantha, Fishbone Thistle, is a biennial that grows about 3 feet high. The edges of its leaves are serrated a little and they are smooth with silvery lines above and covered with whitish down beneath. Its flowers are purplish with ivory colored spines. C. occidentale is also a biennial that grows up to 3 feet high. It has white fuzzy leaves and reddish or purple flowers.
POTTING: These plants can be grown in regular garden soil, however, they prefer moist, fertile, sandy soil. The soil should have good drainage because they won't survive in saturated ground.
PROPAGATION: Increase these plants by division in the spring, basal shoots in the summer, or seeds in early summer.
VARIETIES: C. Rivulare atropurpureum; C. Diacantha; C. occidentale.