There are thousands of rose varieties, and the rose is one of the most popular flowers because of its delicate beauty and sensual fragrance. The term rose "bush" can be applied to any of the rose varieties. From shrub to hybrid tea to climbers, they all come from the same genetic background, but their growth habits have changed over the years.
Bush roses can grow from 2 to 6 feet tall. There are several classes of bush roses, including floribunda, hybrid tea, polyantha, antique, tree and grandiflora. Also included in the bush roses are miniature roses, which grow only 6 to 24 inches tall.
Floribundas are a cross between a hybrid tea and a plyantha. Their flowers bloom in clusters, and the plants make excellent informal hedges. Hybrid teas are the standard cut rose sold by florists. Their flowers are a single bloom on a sturdy stem. Polyanthas bloom in large clusters and are similar (though smaller) to climbing roses. Antique or old-fashioned roses are very fragrant but have a less formal shape than newer varieties. Tree roses are popular bush species grafted onto upright trunks. Grandifloras are a larger bush than the hybrid teas, but their blooms are smaller.
Shrub roses, which can grow up to 10 feet tall, are some of the easiest roses to grow. They need very little--or even no--pest control. They will thrive with little attention. Shrub roses are excellent landscape plants because they spread without being invasive, and they bloom throughout the season. The easiest-to-grow shrub rose is the Knock Out, which has outstanding disease resistance.
The canes of climbing roses may reach 20 feet long or longer. They need to be trellised, grown on a wall or allowed to climb a tree or other support. One subset of climbing roses is the ramblers. Ramblers are fast-growing and easy to grow. They flower only once a season, producing small blooms in large clusters. Everblooming climbers are relatively winter hardy. They have larger flowers than the ramblers, but smaller clusters.