Mimulus cardinalis

©1999

SCARLET MONKEY FLOWER
Family: Scrophulariaceae
Pronounced: MIM-yoo-luss kar-din-AL-iss

GROWING GUIDE

Geographic Origin: Western U.S. to Mexico.
Plant Group: Perennial.
Hardiness: Sunset zones: 4-24. USDA zones: 6-9.

©1998

Mature size: Height: 3 feet (90 cm). Width: 2 feet (60 cm).
Flowering period: July to October.
Flowering attributes: Tubular, scarlet flowers with yellow markings in the throat.
Leaf attributes: Sharply toothed and sticky, light green leaves.
Growth habit: Creeping.
Light: Partial shade.
Soil: Fertile, very moist, humus rich soil. Keep moist in winter.
Feeding: Apply a complete organic fertilizer once a month from spring to early summer.
Propagation Methods: Sow seed in early spring or in autumn and winter over in cold frame. | Divide in spring.

Rainy Side Notes

This perennial barely reaches into the Pacific Northwest via Southwestern Oregon. We proudly claim this brightly colored flower as a Northwest native. Mimulus cardinalis inhabits shady, wet places from streamsides to seepages. The plant spreads by rhizomes and in wet areas where it thrives, it forms good size colonies. In my garden where I grow it in a drier position, it does not spread as much, but does reseed in my gravel walkways.

Bees pollinate most mimulus, but M. cardinalis’ pollination is the task of the hummingbird. This hummingbird magnet is quite noticeable while in bloom with its bright scarlet color.

This species, along with M. lewisii, is being studied for mutations that help species evolve. Researchers studying pink and red flowers in species of mimulus have found some answers: “A single mutation can recruit a whole new set of pollinators, serving as the fork in the road that leads to a new species,” an article in National Geographic states¹.

Scientists are cross breeding these two species that don’t normally cross-pollinate in the wild because the red of M. cardinalis attracts the hummingbird and the pink of M. lewisii attracts the bumblebee. The crosses are producing variations in color that can attract both pollinators. If a natural mutation produced a different color in either of these species, it could prove beneficial. If one or the other pollinators declined, the flower would still be pollinated.

Common Checkerspot and Buckeye butterfly caterpillars feed on the foliage.

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