Hibiscus (hy-BISS-kus) Common Name:  Perennial hibiscus, rose mallow Light:  - Full sun to part sun Soil:  Loamy to rich, evenly moist in summer, well-drained in winter Moisture:  Consistently moist in summer, dry in winter and early spring Blooms:  Late summer Zones:  4 - 9 -*-

Hibiscus 'Fireball' PP#13631 Hibiscus 'Moy Grande'

Hibiscus Description and Cultural Information

When most people think of Hibiscus they think of the tropical plants growing in warm climates like Hawaii or Southern Florida and sold at garden centers around the country as patio and house plants. But that isn't what we are talking about here. These are true, cold hardy perennials that die back each winter only to reemerge in the spring even bigger and better.

Hibiscus coccineus, scarlet rose mallow. 5 - 10'. This plant has narrow, palmate leaves and 5", thin-petaled, deep red flowers. Zones (6) 7 - 9.

Hibsicus moscheutos, common rose mallow. 4 - 8'. This Hibiscus has oval to heart shaped leaves with 6 - 8" white flowers with a red center. 'Mallow Marvels' is a mixed hybrid of white, pink, or red flowers. Zones 4 - 10.

Hibiscus hybrids: There are many hybrids on the market with very large flowers and some very dramatic foliage that were hybridized by the Fleming brothers of Nebraska. 'Old Yella' grows 3' tall with pale yellow to cream flowers up to 12" across. 'Kopper King' PP#10793 is a dramatic plant growing 3' tall with maple-like copper-red foliage and large, 12" white flowers with a red eye that streaks out from the center. 'Fireball' PP#13631 has strap like foliage with burgundy tints and grows about 4' high and wide with large bright red flowers. 'Fantasia' also grows 3' and has maple-cut leaves with 8 - 9" lavender flowers. 'Plum Crazy' PP#11895 grows 3 - 4', has maple cut leaves, and produces 7 - 8" pale plum flowers with purple veins.

Those hybridizing efforts have been continued by Clarence Falstad of Walters Gardens and some of his introductions include Hibiscus 'Cranberry Crush' PP#21984, 'Midnight Marvel' PPAF, 'My Valentine' PPAF, and 'Summer Storm' PP#20443, to name a few.

Older hybrids are also still valuable garden additions. 'Anne Arundel' has 9" pink flowers on 4 - 5' stems. 'Turn of the Century' has bicolored red and pink flowers on 6 - 8' stems. 'Lady Baltimore' has pink, cone-shaped flowers with a red center on 4' stems. 'Lord Baltimore' grows 4 - 5' with 10" brilliant red flowers. 'Moy Grande' has very large, 12" magenta rose flowers over clean, soft green foliage reaching 5' high or more. The petals of 'Moy Grande' don't overlap so the flowers are more lobed than rounded and the foliage is highly resistant to the hibiscus sawfly so it looks great all season. Zones 4 - 9.

How to Grow:  H. coccineus, H. moscheutos, and H. moscheutos var. palustris are sometimes listed as swamp hibiscus or marsh mallows in various reference books, and although they all enjoy lots of moisture while actively growing, most prefer to be on the dry side while dormant, especially in the spring before they sprout. Plant perennial hibiscus in evenly moist, humus-rich soil in full sun or light shade. When growing in heavy, wet soil (such as clay) build up the soil so the crown is somewhat high and dry. Once established they have extensive root systems and are very drought tolerant but enjoy deep watering in the summer for best flower production. In too much shade plants become leggy and more susceptible to insect damage. Japanese beetles love to attack the flowers and the hibiscus sawfly loves to eat the foliage. Dusting with Sevin or spraying with Orthene two to three times per year can help prevent damage. Propagate younger clumps by digging and dividing in the spring, but older plants may become so large they become difficult to move. Propagation can also be done with stem cuttings, which root quickly, in early summer, and plants easily grow from seed.

Landscape uses:  Hibiscus are very large plants of shrublike proportions. Use them as foundation plants or as focal points in large perennial gardens. Combine them with summer blooming plants like Helianthus, daylilies, lilies, Echinacea, Rudbeckia, Salvia, or Agastache or plant them with evergreen shrubs and ornamental grasses so that there is good winter interest after the Hibiscus die back.