Perennial hibiscus (Hibiscus moscheutos) is commonly known as rose mallow or dinner plate size hibiscus. Blooms measure a huge 7-9 inches across. Plants are exceptionally hardy, and can withstand winters as cold as zone 4 (-20°F to -30°F) in Minnesota (zone 4) and the heat of zone 9 (20°F -30°F) in Florida. Each flower lasts only one day.

Summerific® rose mallows are a huge improvement. Older varieties tended to produce flower buds only at the tips of the branches and bloomed for just a few weeks. Plants produced fewer flower buds.

Newer varieties in the Summerific series produce flower buds all up and down the stems, including the top. Newer Summerific varieties are bred to bloom for months, 3 times longer than older varieties.

Rose mallows need water and lots of it. Plants can actually grow in standing water. Grow them within reach of a hose or sprinklers and irrigate on a regular schedule. Whether you are growing in average soil or in a good garden loam, do not allow plants to wilt and dry out. Badly wilted plants may drop their lower leaves and flower buds.

Give them room to grow. Rose mallows are very robust growers that fill their space in the garden. Read the plant label about variety spacing. Dwarf varieties grow at least 3 feet tall and wide, and standard-sized rose mallows grow 4-6 feet tall and wide.

Bring on the sun. Full sun (6+ hours) is imperative. Dark leaf varieties develop a more intense dark purple foliage color in a sunny garden. Full sun equals more flowers. In partial shade, plants produce fewer flowers and dark leaf varieties appear more greenish.

Spring-Summer Perennial Hibiscus Care Tips:

• Cut back rose mallow in the spring. Cut down the dormant woody stems to about 6 inches tall. Rose mallows tend to be one of the last plants to emerge, sometimes as late as early June in northern areas. Newly emerging shoots will grow rapidly, about an inch a day.
• Once spring growth arises, sprinkle slow-release plant food such as Espoma™ Plant-tone^® or an equivalent slow-release organic fertilizer around the root zone (according to package directions. In early summer, follow-up with a water-soluble plant food like Miracle-Gro™ or Jacks™ just as flower buds are beginning to form.