Roses range greatly in size and appearance depending on the type. They offer an appealing form and a pleasing fragrance but often have high maintenance requirements, insect and disease susceptibility and thorns. Knock Out roses, a trademarked variety, offer improved characteristics in some of these areas.

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Most roses have thorns.

Knockout Rose

The Knock Out rose is a type of modern shrub rose. It reaches a height of three feet and develops pinkish-red blooms. It is not one of the thornless roses.

Benefits

Gardeners appreciate the Knock Out rose for its disease resistance and drought tolerance. It also has lower maintenance requirements than many other roses; it does not need to be deadheaded throughout the growing season.

Thornless Roses

Although the Knock Out rose is not a thornless rose, other thornless shrub roses do exist. These include the "Excellence von Schubert," a heat-tolerant rose with an excellent fragrance. The "Cardinal de Richelieu" grows four feet tall, with blooms that last longer than most other roses. The "J.P. Connell" shrub rose is a yellow thornless cultivar that is winter hardy.