About the time they give up on it completely and decide to buy a new one, it begins to grow. Although rose mallow can reach a height of 8 feet, it commonly only grows 3 to 5 feet high, Goodspeed adds. Although it is tall, the stems are generally sturdy enough to hold up the large blossoms, and seldom needs staking. It adapts to most soils, but prefers growing where it is well-drained and rich in organic matter. These perennial plants have striking blooms like the hibiscus, and even similar foliage.
Mallows look a little like a cross between a hollyhock and a hibiscus.
They can vary in size from 6 inches to about 6 feet. In general, mallows are a little more wimpy than hibiscus, and tend to die after a few years, Goodspeed says. However, because they reseed, they can survive for many years in a perennial garden. The mallow plant is a bit too leggy and scruffy looking for my own taste. For more information, contact your local USU County Extension office.