ageratum

Ageratum is a genus of annual and perennial herbaceous flowering plants in the family Asteraceae. The genus is native to the Americas, with most species originating in Mexico and Central America, though some are found in the United States and South America. The most commonly cultivated species is Ageratum houstonianum, known as flossflower or Mexican ageratum. This species is widely grown as an ornamental plant for its fluffy, usually blue, purple, or white flower clusters.

Ageratum plants typically grow to a height of 15 to 60 centimeters (6 to 24 inches), depending on the variety. They have a somewhat sprawling habit and produce opposite, toothed leaves that are often fragrant. The flower heads are composed of numerous small, tubular florets, giving them a soft, cotton-like appearance. The blooming period is generally from early summer until the first frost. Ageratum is a popular choice for bedding plants, borders, containers, and cut flower arrangements. It thrives in full sun to partial shade and well-drained soil. The plant is relatively low-maintenance, requiring regular watering and occasional deadheading to encourage continuous flowering. Several cultivars have been developed, offering variations in flower color, plant size, and growth habit. The genus name "Ageratum" derives from the Greek word "ageratos," meaning "ageless," referring to the flowers' ability to retain their color for a long time.