Found along streams, ponds, in swamps, and wet meadows square stem monkey flower spreads by rhizomes and self-seeding.
FIRST IMPRESSIONS: Mimulus ringens is a multi-stemmed bushy perennial wildflower. The square light green stems are clothed in pairs of clasping lance shaped leaves. In summer, blue-purple flowers are displayed in the upper leaf axils. The blooms are asymmetrical with 2 lips and are reminiscent of garden snapdragons. Hummingbirds and various insect pollinators visit the blooms in wetlands or sunny moist or wet gardens.
HABITAT & HARDINESS: Mimulus ringens occurs in most of the southern Canadian provinces and throughout the contiguous United States except for 5 western states and Florida. Distribution is great in the flood plains of the upper Mississippi River basin and sparse in the southeastern and western United States.
Plants are indigenous to bottomland forests, seeps, swamps, wet meadows, prairie swales, muddy margins of creeks and ponds and drainage ditches. Preferred habitats are generally prone to seasonal flooding or have accumulated standing water.
Plants are hardy from USDA Zones 4-9.
PLANT DESCRIPTION: Mimulus ringens is a rhizomatous upright perennial with multiple smooth square stems.
Pairs of opposite sessile leaves clasp the stems. The leaves are bright green and average 4” long and 1” across. Blades are lance shaped or oval with a pointed tip, smooth surface and serrate margin.
In mid-summer solitary flowers form in the leaf axils of the upper and middle stems. The blue-violet blooms are about 1” across. Flowers have an upper corolla lip with 2 lobes and a larger swollen lower lip with 3 lobes. Each flower has a yellow throat. The curious flower shape reminds some of a monkey’s face.
After the 4-6 week bloom period, rounded capsules full of tiny seed form.
Plants are 1-3’ tall with an average 1’ width.
CULTURAL & MAINTENANCE NEEDS: Mimulus ringens prefers sunny sites with rich loamy wet to moist soils.
Plants tolerate partial shade, sand, clay and temporary standing water but do not tolerate drought.
This species is pest resistant and foliage is unpalatable to deer.
Plant size varies depending on soil moisture and fertility with larger more robust plants in wet fertile situations.
Plants will self-seed. They also expand from underground rhizomes but are not aggressive or strong colonizers.
LANDSCAPE USES: Mimulus ringens is an unusual Accent, Grouping or Mass Planting for a Water Garden or wet Meadow. Plants are also used as Butterfly Host Plants and to attract hummingbirds to Wildlife Gardens. This wildflower has Showy Blooms and provides Erosion Control. It can be used in wet areas of Cottage Gardens, Deer Resistant Plantings, Rain Gardens and Low Maintenance Plantings.
COMPANION & UNDERSTUDY PLANTS: Try planting Mimulus ringens in the wetter zones of a rain garden with Asclepias incarnata, Carex stricta, Eupatorium fistulosum, Iris versicolor, Lobelia cardinalis and Senecio aureus.
Chelone glabra would be a worthy companion or substitute for Mimulus ringens. The two plants have similar height and cultural needs. Both host Baltimore Checkerspot caterpillars and have flowers supposedly shaped like animal heads.
TRIVIA: Hummingbirds and bees pollinate the flowers. Only a few species of the strongest bees (like bumblebees) can force their way into the flowers’ closed throats. Caterpillars of Baltimore checkerspot and Common Buckeye butterflies feed on the foliage.
This species was formerly in the Scrophulariaceae (Figwort) family but is now listed in the Phrymaceae (Lopseed) family.