The development of new and improved roses has been constant, for centuries. There is no reason to believe that this quest for new flower colors and forms, continuous blooms, increased hardiness, and disease resistance will abate. But it is difficult to predict what the favorite rose of the future will be. Yet-untried or even unthought-of crosses may produce hybrids of unexpectedly high quality or beautiful form.
Fashion, a notoriously fickle arbitrator, also plays a large role in the development of roses. It is likely, however, that radically new roses will be the offspring of crosses made with species roses that have not yet been the subject of experimentation. These crosses will produce new foliage forms, flower forms, colors, cultural requirements, and degrees of disease resistance. Many rosarians and breeders believe that such crosses are necessary if the rose is to keep its crown as “queen of the flowers.” The extensive inbreeding of the hybrid teas and their descendants has now reached the point where increasing numbers of roses, instead of fewer, are delicate and susceptible to disease. The rose of the future is perhaps being developed by dedicated breeders like the Kordes family in Germany and Sam McGredy in New Zealand, who have done extensive work with crosses of the Scotch rose (R. spinosissima).
Some hybridizers strive for a particular goal, releasing several new cultivars with similar characteristics. One such group is composed of the David Austin roses, named for its British originator. Austin’s roses resemble old garden roses, but they are everblooming. They are hardy and very floriferous, with the appearance and fragrance of old garden roses. Some varieties are ‘Otello’, ‘Wife of Bath’, ‘The Reeve’, ‘Fair Bianca’, and ‘The Squire’.
Another such group has been developed by the House of Meilland, the famous French breeders who developed ‘Peace’ and many other hybrid teas, grandifloras, and floribundas. The Meidiland roses are designed to be the perfect landscape roses—easy to grow, needing little attention or pruning, and disease resistant. They can be sheared as hedges, and they are even resistant to highway salts when planted in median strips. They bloom heavily in massive clusters. ‘Bonica’, the 1987 All-America Rose Selections (AARS) winner, is the best known of this group. Other cultivars are ‘Sevillana’, ‘White Meidiland’, ‘Scarlet Meidiland’, and ‘Pink Meidiland’.
Up until the mid-nineteenth century, hybridizing was a rather haphazard process. For many years the mistaken belief persisted that a rose inherited its primary characteristics from the seed parent, and the pollen parent had little influence. It is now known that products of crosses take characteristics without favoritism from both the pollen parent and the seed parent. Which characteristics will be carried by the offspring and which will be rejected is the gamble in every cross. Complete and accurate records were seldom kept, and it is now close to impossible to determine the ancestry of most early hybrids.
Modern hybridizers keep careful records and take advantage of current botanical and genetic knowledge. Add to this a dose of imagination, persistence, and a large measure of good luck, and you have a rose breeder’s qualifications. Most of the roses available now have been produced by about fifty professional hybridizers in about a dozen countries. In the course of developing new cultivars, each of these hybridizers cross-pollinates literally thousands of roses a year, collecting tens of thousands of seeds. The number of possible new genetic combinations is immense; however, the odds are about 10,000 to 1 against any specific cross-fertilization producing an outstanding new rose.
The development of new roses is not left entirely in the hands of the professionals. Those fifty or so professional breeders are joined by numerous amateurs, some of whom beat the odds and produce an award-winning and commercially successful rose.
Testing
A rose hybridizer must be patient. From the time a promising rose is developed, 10 years or more may pass before the rose is introduced to the public. A rose company may evaluate seedlings from as many as 600 different new roses each year. Ninety-five percent of them originate within the company or come from professional hybridizers. From this initial cull, 25 to 30 will be deemed worthy of further observation. Of these, a dozen or so are kept for more trials, which may last as long as five years. After this, only four or five will be chosen for public introduction.
Since introducing roses to the public represents a considerable investment in growing space, time, labor, and promotion, the commercial rose nurseries must select those that will do well in all the varied and sometimes extreme climates across North America. To this end, they field-test the roses in test gardens throughout the United States.
During these years of testing, the flowers are rated on such factors as petal count, form, resistance to rain, color, repeat bloom, and fragrance. Disease resistance, hardiness, foliage, and growth habit are also judged. A rose that does well in most categories will be marketed.
Patents
Until the passage of the Townsend-Purnell Plant Patent Act in 1930, a hybridizer could invest in the development of a new rose and then reap few rewards. As soon as a plant was released, it could be propagated by anyone. The Plant Patent Act protects newly developed plants in the same way that industrial inventions are protected. The patent owner is given proprietary rights to the plant for 17 years. During that time the owner is entitled to a royalty for every offspring of the plant. Thus, the rose hybridizer can recoup development costs and perhaps even make a little profit. Commercial rose nurseries often purchase licenses from the hybridizers to propagate and sell particular cultivars.
The law requires that all patented roses be identified by a patent number engraved on a tag attached to the plant. Do not buy roses sold as patented unless they carry this identification tag. It is your guarantee that the plant will perform as the cultivar advertised.
Cultivar Names
Before a rose is ready for its public debut, it needs a name. The hybridizer or distributing nursery chooses the name and, in the United States, registers it with the American Rose Society, designated by the International Horticultural Congress as the International Registration Authority for Roses (IRAR). Names too similar to existing botanical or cultivar names are rejected. A name can be reused after 30 years if there is proof that the original rose is extinct, is not of historical importance, and is not a parent of an existing cultivar.