Shrub Varieties Proliferate
Many kinds of shrub roses have been introduced in recent years, especially the ground covers, such as 'Cliffs of Dover', 'Flower Carpet' and 'Jeepers Creepers'. These are ideal for slopes and large vistas. In smaller gardens, try them as specimens in containers and hanging baskets. There are also new shrub roses that are reliably hardy in cold climates. The Morden and Explorer series are hardy to -25°F, and there are repeat-blooming varieties of Rosa rugosa that are hardy to -30°F.
At the other end of the spectrum are David Austin's English roses. Although lacking the ironclad constitution of the sturdiest shrubs, these new roses combine the fragrance and shape of old-fashioned roses that bloom once per season with a modern reblooming habit.
Finally, there are numerous roses that don't easily fit any existing category or group. These include 'Iceberg', 'Lady of the Dawn', 'Simplicity' and 'Festival Fanfare'. Officially classed as floribundas (shrubbier versions of a hybrid tea), these roses meet or exceed all requirements of a shrub rose. Another example is 'Magic Carpet'. Classed as a large-flowered climber, it serves beautifully as a ground cover.
Older roses that fit the shrub category include the Kordesii, musk and Buck hybrids, ancestors of some of the new shrubs listed here. Kordesii hybrids include the eight-foot-tall 'Dortmund'. It's hardy to -15°F and is very disease resistant. The nearly everblooming musks like 'Buff Beauty' and 'Kathleen' grow five to 10 feet tall and produce two-inch fragrant flowers in clusters; plants are hardy to 0°F. Buck hybrids, such as 'Apple Jack' and 'Prairie Princess', grow three to five feet high and are hardy to -15°F.
To be honest, I love hybrid teas, and I will probably always grow them. No other type of rose offers such beautifully shaped flowers on long, cuttable stems, and many are highly scented. Many modern shrub roses, products of the environmental awareness of the early 1970's, don't require spraying, and that's good. But notable exceptions (such as the David Austin's) aside, I've noticed that few offer much in the way of fragrance, or make extra-long, elegant stems.
Buying and Planting
Shrub roses are sold in the traditional ways. If you purchase your roses mail order, they will arrive bare root. Most mail-order nurseries ship in early spring, and the roses should be planted immediately -- don't let the roots dry out. If mail-order source can be persuaded to ship in the fall, planting then will give roses a head start in the spring. Be certain to cover canes of fall-planted roses with soil prior to freezing weather.
All the shrub roses listed here need at least eight hours a day of full sun for maximum flower production and well-drained soil.
Once you've selected a site, dig a hole wide enough to extend the roots of a bare-root plant without bending them. Spread the roots over a low cone of soil in the center of the planting hole. Backfill with the soil removed from the hole, firming it in place with your hands.
If you buy your plants at a nursery or garden center during the growing season, they will be growing in containers. The advantage of buying this way is that you see the plant in leaf or even in bloom. When transplanting a potted rose to the garden, dig a hole that is twice the width and about the same depth as the container (see "Hardiness" below for exceptions). Use a utility knife to cut the pot away so that the roots are disturbed as little as possible.
Roses need water, although once established, shrubs require less than a hybrid tea. If you live where rainfall during the growing season is slight or nonexistent, give the young plants a deep, thorough soaking once or twice weekly through the summer. For optimum growth, fertilize in early spring, late spring and early fall with either organic fertilizer, fertilizers formulated specifically for roses, or both.
Most shrub roses are "self-cleaning," meaning faded flowers drop and plants generally look neater. Deadheading or cutting off faded blooms is not necessary. Prune to shape or to cut flowers for indoors any time of year. In spring, remove dead wood, and if necessary, shorten two- and three-year-old growth or extra-vigorous growth by one-third to one-half.
If you live where winter temperatures are 20°F or above, plant at the container depth or so that the bud union of grafted roses (the swollen area between the roots and where the plant branches) is at soil level. Unless otherwise noted, most roses die to ground level at temperatures around -20°F. Where winter temperatures range between 20° and -20°F, set the bud union deeper, two or more inches below the soil surface.
In climates where winter temperatures reach lower than -20°F choose nongrafted roses grown on their own roots. "Own-root" roses are more likely to survive and regrow after severe cold. Several are available. These include the Morden and Explorer series, and specific varieties, such as 'Simplicity'.
Plant own-root roses at the previous soil line, indicated by the color change on the thick shank above roots. (All of the hardiness figures offered here are based upon a healthy, vigorous rose. Weak and poorly growing plants are less cold-tolerant.)
Climate has another important effect on rose performance. Roses growing in sunny, temperate regions tend to become larger than stated in some catalogs. For instance, 'Sally Holmes' and 'Lady of the Dawn' are essentially climbers in warm, southern regions, but are medium-sized shrubs in the North.
There's been a revolution in the world of roses, and it's good news for gardeners. There is a renewed interest in roses of all kinds, and a more liberal sense of their landscape possibilities. No longer confined to the rose garden, these roses are freely integrated into the landscape, according to their size and shape. Much more so than just a few years ago, I see them used as garden plants -- in perennial borders, aligned in rows for colorful screens or borders, spilling out of hanging baskets, blanketing fences and posts and massed for ground cover.
Please keep in mind that all roses are, technically, shrubs. Furthermore, the terms "shrub rose" or "landscape rose," are loose designations and can include rose varieties from almost any class. Those I focus on here all grow into healthy, well-shaped shrubs without much attention to pruning or training required.
The characteristics of a good shrub rose are simple to list:
You can buy and plant container-grown roses now, or order bare-root roses now and plant this fall or early next spring. Many nurseries sell blooming shrub roses in containers, just like any other landscape plant.
I polled rose experts throughout the U.S. to create the following list. Roses are arranged by height, beginning with the low-growing ground cover kinds. Because of distinctions other than size, own-root, rugosa and David Austin roses are listed separately. All are widely available, low-maintenance, profuse bloomers that are rarely bothered by pests or diseases.
The brief descriptions include some shorthand words: "single" flowers have five petals and showy stamens; "semidouble" flowers have five to 15 petals; and "double" flowers have 20 to 50 petals or more. Flower size is the diameter of a fully open blossom. All are self-cleaning, except those noted as "ND," which means the faded flower need deadheading.
Hardiness temperatures are approximate, mostly because other factors in addition to actual temperature affect hardiness; exceptions from norms are noted. (You might also factor into your calculations that yellow roses of all types are usually less hardy than other colors; 'Aicha' is a notable exception.) Plant dimensions, also approximate, are given as height followed by width.
1. Ground Cover Roses. Mass these low-growing roses to cover banks or large areas, or accentuate their trailing.
2. Medium to Tall Roses. These medium to tall roses produce single stems or canes that grow four to 10 feet tall. Use them to anchor perennial borders, as specimen plants and to make informal hedges. All are repeat bloomers and most are hardy to -15°F.
Oranges or Blends
3. Own-Root Roses. Rely upon these nongrafted roses that grow on their own roots if you live where winter temperatures reach -20°F and colder. Check with your local nursery: Those listed here are always on their own roots, but some roses are available both ways. For instance, all bare-root ground cover and shrub roses from Jackson & Perkins grow on their own roots, but the same J&P varieties sold packaged or in containers are grafted.
4. Rugosa Hybrids. Among the most cold hardy of all roses (to -30°F) are some of the newest and most exciting varieties. All are repeat-blooming shrubs with simple, sometimes fragrant flowers, attractive fruits and hardy, disease-free foliage.
5. David Austin's English Roses. These roses have become widely grown in the U.S. in just the last decade. More than 50 varieties are currently available. All are modern hybrids with old-fashioned, often strongly scented flowers. The flower size and fragrance comes at a price, however; these roses are not disease-free as other shrub roses and are only cold hardy to around 0°F. The following list includes some of the most flowerful and disease-resistant varieties.
Yellow or Apricot
Karen Dardick's Los Angeles home is surrounded by roses of all kinds. Her current favorite is 'Sally Holmes'.
Photography by Ferguson-Carass.