Blue-Stemmed Goldenrod (Solidago caesia) or Wreath Goldenrod, is a woodland perennial which occurs in woods, bluff ledges and bluff bases. Typically grows 1.5-3 feet tall on arching, glabrous, wiry, greenish-purple stems which are covered with a silvery-white waxy bloom that can be rubbed off. Tiny, bright yellow, daisy-like flowers typically with 3-4 rays per head appear in a series of loose clusters in the leaf axils along the length of the stems, with the terminal clusters being the largest.
The blooming period occurs from late summer into the fall, lasting about 1 month. Fertile florets are replaced by small bullet-shaped achenes that are finely pubescent. Each achene has a small tuft of hairs. The achenes are distributed by the wind. The root system is fibrous and rhizomatous. Occasionally, small loose colonies of plants will develop at favorable sites.
Habitats include upland woodlands, woodland openings, bluffs, upper slopes of ravines, and rocky cliffs in shaded or partially shaded areas. This species is usually found in higher quality habitats consisting of upland woodland areas where deciduous trees (especially oaks) are dominant.
This distinctive goldenrod is both elegant and shade-tolerant. Easily grown in average, dry to medium, well-drained soils in full sun to part shade. A woodland species that tolerates poor, dry soils and light shade, but performs best in full sun. During dry weather, some of the lower leaves may wither away, otherwise they usually remain in good condition. This species is primarily clump-forming and does not spread aggressively
Goldenrods have been wrongfully accused of causing hay fever which is actually an allergic reaction to wind-borne pollen from other plants such as ragweed.