An annual with a dwarf, mounding habit, monkey flower (Mimulus x hybridus cultivars) enjoys shade and water. It grows comfortably along stream beds or even in boggy conditions, and it provides pockets of bright color in border gardens from late spring to fall. Mimulus cultivars bloom in yellow, cream, orange, red, and white, often with blotches or spots in contrasting colors.

Plant Facts
Common name: Monkey flower
Botanical name: Mimulus x hybridus cultivars
Plant type: Tender perennial usually grown as an annual
Height: 5 to 12 inches tall
Zones: 9 to 10
Family: Scrophulariaceae

Growing conditions

  • Sun: Full sun to light shade
  • Soil: Humus-rich, well-drained soil
  • Moisture: Consistently moist; never allow plants to dry out.


Care

  • Mulch: Apply organic mulch over plant roots to maintain even moisture.
  • Fertilizer: Mix a slow-release fertilizer into the soil before planting. Choose one with more phosphorus than nitrogen, such as 15-35-15, to encourage better blooming.
  • Pruning: Deadhead regularly.


Cultivars

  • ‘Maximus Mix' has blooms that measure 2 ½ inches across. It performs well in warmer conditions than some cultivars. Grows 11 ½ inches tall.
  • ‘Calypso' is a mix with single-colored, bi-colored, and spotted blooms in orange, yellow, burgundy, and pink. Grows 5 to 9 inches tall.
  • ‘Magic Yellow Flame' has golden yellow blooms with orange spots. Grows 9 inches tall.
  • ‘Monkey Magic' has 2-inch, white blooms with red spots. Grows 9 inches tall.


Garden notes

  • Monkey flowers are not frost-tolerant, but they like cool, moist summers.
  • Will grow well in wet, low-lying areas in the garden.
  • Light afternoon shade prolongs bloom.
  • Use in borders, rock gardens, and containers.
  • Pests and diseases
  • Downy mildew, powdery mildew, and gray mold occur.
  • Spider mites and aphids attack them.


Propagation

  • Sow seeds inside four to six weeks before planting out. Do not cover seed, and provide light and bottom heat of 70ºF to 75ºF. Germinates in 7 to 21 days.
  • Transplant into garden two weeks after final spring frost. Plant 6 inches apart.
  • Cultivar seeds usually will not come "true" when collected from flower beds.


All in the family

  • Mimulus x bartonianus is an upright perennial with sticky, green leaves. Blooms are pink to rose-red with rust-colored spots and yellow throats. Grows 24 inches tall. Hardy in Zones 8 to 10.
  • M. cardinalis (scarlet monkey flower) is a creeping perennial with tubular red flowers. Grows 36 inches long. Zones 6 to 9.
  • The Scrophulariaceae family includes the perennials Angelonia angustifolia, turtlehead (Chelone spp.), foxglove (Digitalis spp.), Penstemon spp., mullein (Verbascum spp.), and speedwell (Veronica spp.).


Text by Mary Pestel, photo courtesy of National Garden Bureau.