Aruncus dioicus (ah-RUN-kus dye-oh-EE-kus), or goatsbeard, is an impactful perennial able to thrive in a wide array of conditions, not to be confused with Astilbe. Goatsbeard, of the rose family, Rosaceae, is native to deciduous woodlands of eastern and central North America including Minnesota’s neighboring states of Wisconsin and Iowa, as well as western Europe and southeastern Asia in the case of the dwarf species.
Despite its large, shrubby appearance, goatsbeard is an herbaceous perennial, slowly spreading by rhizomes to form lush clumps of pinnately compound leaves, each composed of twenty or more toothed leaflets. Aruncus is somewhat slow to establish, ultimately reaching a mature size of 36-48” tall and wide over a few years. Blooming in late spring through early summer, Aruncus produce massive feather-like plumes upwards of 18” long with numerous small ivory white flowers. While never distinguished, goatsbeard is dioecious, meaning there are distinct male and female plants, with male plants producing slightly showier blooms than female plants due to their numerous stamens per flower, while female blooms only have three stamens per flower. After blooming, goatsbeard may be pruned back to promote dense, bushy growth through the remainder of the season, or left alone for dried interest.
Preferring moist, well-drained soil in part sun, goatsbeard is deer and rabbit resistant, tolerant of most site conditions, including full sun or full shade, as well as clay soils or consistently wet areas, and is intolerant of drying out completely.
Aruncus create an incredible backdrop for shade gardens, planted in mass groupings, along ponds or streams, or in woodland gardens. In addition to the native species, ‘Misty Lace’ offers a more compact habit with red stems, reaching a mature size of two to three feet tall and wide, a hybrid of Aruncus dioicus and the Korean native dwarf goatsbeard, Aruncus aethusifolius.
Unlike its large and stately relative, dwarf goatsbeard is excellent for shady edging, low borders, or massed as a shady groundcover, reaching a mature size of 6-12” tall and wide. Sharing similar site preferences to goatsbeard, dwarf goatsbeard has deeply lobed, fern-like foliage with small ivory plumes rising well above the foliage. In the fall, Aruncus aethusifolius continues the show with showstopping orange and yellow fall color.