Roses in this class go under a variety of names: ground cover roses, climbers, ramblers and pillar roses. The common thread is that all of them have very long canes that can be directed along the ground or over structures. No rose truly climbs, as they don't have tendrils or other devices to help grasp on supports. Many of the climbers offered in garden centers are sports or mutations of standard hybrid teas. As a result, their hardiness is very questionable in colder climates, where they often freeze to the ground each year. As a result, the reason gardeners grow climbers–to cover a structure–is lost; the process has to start new each year. Climbers and ramblers are distinguished by their bloom and growth habit. Climbers generally bear large flowers singly or in clusters on very heavy canes. Many climbers have periodic rebloom in late summer or early autumn. In addition, the more horizontal a climber can be trained, the more blooms it will produce. Climbers range in height from 8-25 feet. Rambling roses are almost all once-blooming with small flowers in large clusters. The canes are generally very slender, flexible, and easily trained. Ramblers get very large, often growing to 15-25 feet. Rambling roses were favorites with Victorian gardeners.
Gardeners in colder climates often have fewer choices when selecting climbers due to the difficulty of successfully overwintering the long canes. There are a number of excellent hardy 'Kordesii' and 'Canadian Explorer' types grown as climbers that overwinter very nicely. A number of roses found in the other classes can be treated as climbers, pillars, or groundcover roses by virtue of the fact that they have long canes that with support can be trained upward.