We are well into bare root rose season, which began in January and continues to May. This is a good time to add roses to the landscape: mail order nurseries and garden centers offer lots of rose varieties at the year’s best prices, and gardeners can plant bare-root roses now for summer blooms.
Inventories are of course limited to the number of plants that nurseries have developed, so selections narrow as the season progresses and the most desirable varieties sell out the earliest, so choose and buy your roses early.
This is the time when gardeners plan to add roses to their gardens. To begin, let’s review the three major kinds of roses that might be included in the garden.
The earliest group chronologically is the species roses, often called wild roses. They occur in nature, prior to human cultivation or hybridization. There are more than 150 species of wild roses; one species, Rosa chinensis, was developed by breeders into many of the rose varieties found in today’s gardens.
Then, of the cultivated roses, we have the old garden roses, most of which are native to Europe, while some Asian varieties were added later to this category. Several varieties are included in this category, but almost all have the characteristic of blooming only once during each season.
The third category is called the modern garden roses, defined as varieties bred after 1867, when two old garden rose varieties (Hybrid Perpetuals and Teas) were combined. Many roses in this category have old garden roses (especially Asian varieties) in their background, and they typically have repeated blooms during each season. The most popular among the modern roses are hybrid tea roses, which occur in a large and growing diversity of blossoms.
In addition to the hybrid teas, there are several other modern roses: polyantha, floribunda, grandiflora, miniature, climbing & rambling, English, landscape, plus a few less common kinds.
Each variety within the species, old garden roses, and modern garden roses categories has unique qualities, clearly deserving book-length treatment, so for this column let’s consider the broad concept of landscaping with roses.
When we say “landscaping,” we refer to the relationships among plants, between plants and spaces, and between plants and their garden surroundings, e.g., houses and other structures.
Landscaping with roses differs from collecting roses, which is a popular activity for some gardeners, given the abundant options within the genus Rosa. Rose collections are often grouped in rose gardens, which for some gardeners find convenient for cultivation, maintenance (pruning), and comparison of the specimens. Rose collections could also be dispersed among other plants in the garden.
The elements of landscaping with roses are the three major forms of rose plants: bush, shrub, and climber.
Bush roses
These are relatively small, compact varieties that can be grown in large containers, used as groundcovers, or filling smaller spaces in the garden. Some bush roses are marketed as landscape roses; these are maintained easily by pruning by two-thirds at the end of the bloom season. An example of a bush rose in my garden is ‘Pink Supreme’, one of Flower Carpet series by Tessalear Plants (tesselaar.com/plants/flower-carpet-roses/).
Shrub roses
This very popular form includes relatively large, upright varieties growing from about three feet to 6 feet tall, or even larger. As always, it’s good to learn the mature size of a rose plant before placing it in the landscape. Shrub roses are most widely offered by garden centers and mail order nurseries, and are available in many blossom colors, sizes, and forms, as well as a range of overall sizes. There are numerous large and small growers of shrub roses, including familiar companies, such as Jackson & Perkins, Weeks, David Austin, and Kordes.
Many shrub roses have been grafted onto the roots of a different rose to enable rapid development from cuttings. A widely used rootstock (or understock) rose is ‘Dr. Huey’. Grafting makes more roses available faster than rooting cuttings of hybridized varieties. The downside of grafted roses is that the rootstocks develop their own branches (“suckers”) from below the graft. These growths drain nutrients and energy from the selected variety and should be removed. The recommended practice is to tear the sucker from the rootstock, rather than just cutting it above the soil level.
The alternatives to grafted roses are roses grown on their own roots. For information about such plants, visit www.heirloomroses.com/info/about-own-root-roses.
Climbers and ramblers
This third major form of rose plants include plants that have longer stems and canes than shrub roses. Unlike vines, these roses do not use tendrils or twining ability to support their canes but must be attached to a trellis or other structure for best growth and floral display. These plants produce their most blooms on lateral branches, so they should be located where a trellis structure could support the desired width for the plant’s mature size and pruned to encourage more horizontal branching.
Climbers and ramblers are different in at least two ways. Climbers are repeat bloomers, while ramblers flower only once each year. Also, flowers and leaves grow in clusters of five on climbers, and in clusters of seven on ramblers.
My garden’s climbing roses: ‘Graham Thomas’, a highly rated David Austin rose with deep yellow flowers; ‘Polka’, with large apricot and apricot blend flowers; and two Kordes roses: ‘William Baffin’ (deep pink) and ‘Dortmund’ (red blend).
I have just one rambling rose, Rosa mulligani, a species from China that produces a great display of single white blossoms. This is a vigorous, large plant growing on a wire trellis attached to a fence.
Advance Your knowledge
For an overview of the wide-ranging world of roses, visit en.wikipedia.org/wiki/Garden_roses.
You can benefit from many advice about caring for roses by searching the Internet for “rose cultivation.” If you enjoy demonstrations of various practices, narrow the search by clicking on “Videos” is the menu above the search results.
Some of the larger rose growers have knowledgeable and well-produced online video recordings of cultivation practices. For one example, visit www.davidaustinroses.com/ and click on “Advice & Inspiration.” Visit other rose growers listed above for additional demonstrations.
The American Rose Society’s website (www.rose.org/) offers extensive information about all aspects of rose care. If you are growing roses, now or in the future, this website is well worth exploring, and should be on your short list of online visits.
The internet also serves as a rich resource of ideas and advice on landscaping with roses. One good example is a thoughtful and thorough article from Garden Design magazine, available at www.gardendesign.com/roses/).
Enrich your gardening days
Explore the wonderful world of roses if you have not already engaged with this genus. It offers a vast range of choices to consider, with famously beautiful blossoms in diverse forms, sizes, and colors. The blossoms are long-lasting as cut flowers, while some gardeners prefer to enjoy them as stunning ornaments in the garden. Growing roses always supports the pursuit of personal preferences, and somehow encourages different views on landscaping, pruning and other aspects of cultivation. That’s part of the pleasure of gardening with roses.
Tom Karwin is past president of Friends of the UC Santa Cruz Arboretum, Monterey Bay Area Cactus & Succulent Society, and Monterey Bay Iris Society, and a Lifetime UC Master Gardener (Certified 1999–2009). He is now a board member and garden coach for the Santa Cruz Hostel Society.
Source: www.mercurynews.com