Also called Allegheny monkey flower or square-stemmed monkey flower, this herbaceous perennial is native to North America where it grows in wet soils such as wet meadows, swamps, stream and pond borders, floodplains, and drainage ditches. Plants are erect with square, occasionally branching stems that bear opposite, clasping (sessile) leaves. The medium green leaves are lanceolate to oval, four to six inches long and one inch wide, with widely spaced teeth on the margins and pointed tips. The lilac-blue (occasionally pink or white) flowers are produced in the axils of the leaves on the upper half of the stem over a one and half month period from summer into fall. Each snapdragon-like flower is two lipped, an inch across, bears a yellow patch in its throat, and is thought to resemble to face of a monkey. Flowers are followed by a seed capsule with many seeds that are dispersed by wind or water. Monkey flower is an excellent choice for a bog garden, the wettest part of a rain garden, or any other consistently moist area.
Type: Herbaceous perennial
Bloom: Two lipped flowers in lilac-blue, (occasionally pink or white) in summer into fall
Size: 12-36″ H x 8-12″ W
Light: Part shade to full sun (with adequate water)
Soil: Average, wet to moist
Care: Low maintenance
Hardiness: Zones 3-8
Pests and Diseases: None of significance
Propagation: Seed, division
Companion Plants: Boneset (Eupatorium perfoliatum), Blue vervain (Verbena hastata), Sneezeweed (Helenium autumnale), Swamp milkweed (Asclepias incarnata), Swamp goldenrod (Solidago patula).