Ageratina altissima

White Snakeroot is a herbaceous perennial that can grow to 3 feet. The plant is native to woodland areas in the Eastern United States and typically occurs in rich or rocky woods, thickets, wood margins, and rocky areas. Garden uses include cottage gardens, wild gardens, woodland gardens, and naturalized areas. It may also be effective in shady corners of the border.  

White Snakeroot is easily grown in average, medium to wet, well-drained soils in full sun to part shade. While it does well in dry soil, it prefers part shade in moist, organic soils. These plants have decidedly better shade tolerance than most other species of Eupatorium. The 'Chocolate' cultivar has purple leaves throughout the summer. This is one of the last wildflowers to bloom during the fall.

The root system consists of spreading rhizomes and shallow fibrous roots. This plant can spread by means of its rhizomes, or it can reseed itself into new areas. Because it spreads easily by seed, you should deadhead spent flower heads to avoid any unwanted self-seeding. 

Reportedly, the erroneous belief that an extract of the roots was a remedy for snakebite led to the common name. However, settlers who drank milk from cows that fed on this plant often developed the disease called milk sickness. See information below for toxicity. 

Diseases, Insects and Other Plant Problems:

The plant is susceptible to leaf miners and flea beetles may attack the foliage. Under optimum growing conditions, the plant can spread rapidly through self-seeding and rhizomes. Full sun in a dry situation can cause the leaves to turn yellow and wilt