Meadowsweet is a native erect deciduous shrub with an unbranched stem, growing to six feet in height. Twigs have a yellowish-brown bark, older stems are brown to reddish-brown. There are two varieties.
The leaves are alternate, stalked, varying from a narrow lanceolate shape to more broadly obovate, 3 to 5 times longer than wide, up to 3-1/2 inches long. Bases are wedge shape to rounded, margins are finely to coarsely toothed depending on the variety. There is a main mid-vein with many pinnate laterals (which are not prominent), some laterals ending at a primary tooth. Some leaves many be doubly toothed. Leaf surfaces are mostly smooth.
The inflorescence is a terminal panicle, sometimes narrowly conical and sometimes open depending on the variety. The panicle height is up to 3.5 times the diameter. Additional panicles can rise from the upper leaf axils. Branches within the inflorescence usually have fine short hair. The flower clusters are quite showy.
The flowers are 5-parted with a hemispherical shaped hypanthium which has 5 lobes, broadly triangular at the tips. The outside surface of these lobes may be smooth or fine fine hair. Buds may be tinged with pink. The petals are white, spreading outward, circular in the upper half, then narrowed to the base. Flowers are about 1/4 inch wide. The central receptacle is of 5 carpels, each with a greenish pistil and style. Stamens number 30 to 50, are 1 to 2 times the petal length and are exserted. Filaments are white, anthers are brownish in pollination. There may be up to 4 false stamens (staminodes). There is a colorful nectary ring at the base of the stamens that is yellow to orangish-pink.
Fruit: Fertilized flowers produce a 5-parted smooth capsule of 5 smooth seed follicles, 3 to 4 mm long, each typically containing 2 to 4 small seeds, then opening at the tip for seed dispersal. Seeds are very small and light and need to be surface sown and require 60 days of cold stratification. Fruits provide no winter interest.
Varieties: Two - Var. alba has longer leaves, 3 to 4 times the width, more narrow, with finely toothed margins and an inflorescence that is narrowly conical. Var. latifolia has shorter leaves, 2 to 3 times the width, more elliptical, coarse teeth on the margins and open pyramidal inflorescences. This variety is usually taller overall. The photos shown here are of var. alba.
Habitat: Meadowsweet is found in moist soils with wet to wet-mesic conditions; full to partial sun such as found in wet prairies, open ground along streams, marshy areas. Constant moisture is needed. Dead-heading may produce additional bloom. Shaded plants do not flower.
Names: The genus Spiraea is from the Greek speiraira, a plant used for garlands. The base of this is speira, meaning a spiral or twisted, as in making a garland. The species name alba means 'white' and the variety name latifolia means broad referring to the more elliptical leaf. The author name for the plant classification, from 1772 - ‘Du Roi’ refers to Johann Philipp Du Roi (1741-1785), German physician and botanist who published work on North American trees. His major work was Dissertatio inauguralis observationes botanica. See notes at page bottom about the common name.
Comparisons: Both varieties exist in Minnesota. One is likely to run into the European species, S. salicifolia, which has been imported into North America as an ornamental and thus when it escaped cultivation, it hybridized with S. alba, producing difficult to identify plants. These might typically be found in developed areas and near abandoned gardens. Also found in Minnesota is S. tomentosa. Steeplebush, which looks similar but has pink flowers, hairy seed follicles, far fewer stamens.
Above: The inflorescence is a narrowly conical panicle atop the stem in var. alba. Drawing from Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York.
Below: The flowers have 5 white petals, 30 to 50 stamens well exserted from the corolla. Like many species of the Rose family they arise from a nectar disc in the center of the hypanthium. This varies in color from yellow to orangish.
Below: The hemispherical shaped hypanthium has 5 yellow-green triangular lobes. The new twig on which the flowers have appeared is yellowish and with fine hair.
Below: The leaves of var. alba are 3 to 5 times longer than wide with a finely serrate edge. The under side (2nd photo) is paler but free of long hair - some fine hair on the main rib. Note the pattern of secondary veins.
Notes: In 1908 and 1915 Eloise Butler specified she planted S. salicifolia, the European species, both times from nurseries. In 1912 she simple listed 'Meadow Sweet' without the scientific name, but from a nursery in Solon Springs Wisconsin, so we don't know clearly if that was our native species, Spiraea alba, or if they also provided S. salicifolia. However on Sept. 20, 1917 she noted getting a S. salicifolia from Glenwood Park, which partially surrounded the Garden - and that species does not grow in Minnesota so perhaps it was our native S. alba or it may have been an introduced S. salicifolia. On Curator Martha Crone's 1951 census she listed S. alba and 'narrowleaf'.
Within Minnesota Meadowsweet is found in most counties of the state with the exceptions being in the drier western and southwestern counties. The DNR does not track by variety but the U of M Herbarium reports both varieties found in the State. In North America var. alba is more widespread, found in most states of the NE Quadrant from the Dakotas east, south as far as Missouri and then eastward. In Canada it is found from Alberta to Quebec. Var. latifolia is mostly found along the east coast of the U.S. including all of New England, then west along the Great Lakes reaching down into to Minnesota from Canada, but not Wisconsin. In Canada it is found from Manitoba eastward.
The only other Spiraea found in Minnesota is Steeplebush, S. tomentosa.
Common Name: A number of plants have been given the common name of Meadow Sweet, and principally, as concerns us, is Filipendula ulmaria, best known today as Queen of the Meadow, which Linnaeus originally classified as Spiraea ulmaria. It is important to note that the use of the name 'Meadowsweet' as described for S. alba does not give that plant the characteristics of the other plant - Filipendula ulmaria. Mrs. Grieve (Ref. #7), in writing about F. ulmaria states that the name Meadow Sweet comes from "Meadsweet" and the older Anglo Saxon "Meadwort" which refers to the plant's use as a flavoring agent for mead. It was one of the fifty ingredients in a drink called "Save" mentioned in Chaucer's Knight's Tale, (the drink referred to was Meadwort - a honey-herb wine).
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"