Never before have so many roses been available to gardeners!
For hundreds of years, growers have bred roses seeking to develop the very best. Aggressive breeding for cold hardiness has produced a wider range of roses for Midwest gardens, making it easier than ever to find alternatives to the high-maintenance hybrid tea roses. This is the first time in history that we have such a palette of colors, patterns, and fragrances to choose from. Breeders have also developed roses resistant to diseases, especially black spot, and tolerant of drought.
KNOCK OUT SHRUB ROSES
Knock Out™ rose (which has the scientific name Rosa 'Radrazz') is an outstanding 2000 All America Rose Selections winner. This drought-tolerant, cold-hardy, disease-resistant rose is truly an accomplishment in the rose-breeding industry. It is a 3-foot by 3-foot landscape, or shrub, rose covered with neon cherry blooms throughout its long growing season. While the original Knock Out rose is a cherry red, single-flowering shrub, additional color breakthroughs have been developed in this highly successful series. Look for the cherry red Double Knock Out™, Pink Knock Out™, Double Pink Knock Out™, Blushing Knock Out™, pink and yellow Rainbow Knock Out™, and creamy golden Sunny Knock Out™.
Garden rosarian William Radler, who bred and introduced Knock Out, tested its resistance to black spot by gathering and drying infected leaves from other roses. He then ground these leaves into a powder, which he spread over the leaves of his Knock Out roses. Although black spot is one of the greatest challenges of growing roses, Knock Out showed no spotted, yellow leaves, or defoliation, confirming the fact that it is a strong performer, even when surrounded by infected roses. From a designer's viewpoint, a mass of these red roses complemented by fountain grass (Pennisetum alopecuroides) and lavender-flowered Russian sage (Perovskia atriplicifolia), would create a striking effect in any garden. Find out more about shrub roses in general in Plant Evaluation Notes #11.
Rosa rugosa is a very old species with a long history dating to ancient China. These roses are easily identified by the characteristic corrugated texture of their smaller, deep green leaves, and their old-fashioned, single or double flowers. They are very hardy as well as disease and pest resistant. Rugosas carry a strong fragrance and range in height and width from 2 to 6 feet. Flower colors vary from pure white to lavender and mauve. The big bright red fruit or hips are not only beautiful, but are also useful for making jellies, jams, teas, and vitamins. The foliage turns an attractive reddish orange in fall.
Rosa 'Dart's Dash' is an outstanding medium-sized lavender rugosa that can be pruned as a solid hedge. Another top performer is Rosa rugosa 'Rubra'. Its reddish blooms and ability to tolerate some shade make it invaluable in the home landscape. Rugosas are so tolerant of poor soils and salt that they were chosen as median strip plantings on Lake Shore Drive, where they bloom beautifully from June to October.
Canadian breeders have developed a line of winter-hardy, pest-resistant roses by hybridizing rugosas. Called the Explorer series, each colorful rose commemorates a famous Canadian explorer. 'William Baffin' will push 7 feet of growth its first year. Covered with dark pink flowers from early June to September, it will quickly cover an arbor or fence with beautiful color. Like most of the Explorer roses, it produces orange hips that are retained into winter. 'Jens Munk' is another larger-sized Explorer with medium pink flowers from early June to mid-October.
With such a large selection of versatile roses available, it's possible to find just the right one to suit your garden style as well as your maintenance timetable. A visit to the Chicago Botanic Garden's Rose Garden in spring, summer, and fall will reward gardeners with 5,000 blooming roses — perfect inspiration for your garden plans.