LECTURE

PARADISE TRANSPLANTED Series
Organised by Dr Jennifer Gunning; sponsored by Buro Happold

THE HISTORY AND BREEDING OF THE GARDEN ROSE

A Lecture by Michael Marriott, on 24 July 1998
Michael Marriott is Nursery Manager of David Austin Roses Ltd.

Sweet briar roses, found in the wild, were first planted to protect property from intruders; thorny and tough, they make an impenetrable barrier. Other early uses of roses were also practical, for food, medicines and scent. R. rugosa, from Japan, has been so used and huge amounts of roses are still grown for perfumes made from attar of roses. Petals of R. gallica, another ancient rose, actually increase their perfume as they dry, making them ideal for potpourri, and stuffing pillows.
Wild roses have always produced new varieties either from genetic mutations known as ‘sports’ or from chance cross-pollination by insects. The moss rose is a ‘sport’ from R. centifolia. A good nineteenth century moss is William Lobb with a beautiful fragrance. Winchester Cathedral is a modern example of a successful `sport' from another English rose. Crosses from the European R. gallica and the Asiatic musk rose have been recognised as very early hybrids. After about 1600 the deliberate transfer of pollen began to be practised; by 1629 Parkinson listed twelve distinct varieties of rose, while the Dutch soon produced thousands of varieties.
The Gallicas are the basis of all roses seen today, including the damask, the hybrid tea and the English. Damasks are crosses from R. gallica and R. phoenicia with a tendency to be rather straggly; Ispahan is one of the better behaved. Too stiff a form does not, however, well suit a rose; some floppiness avoids an artificial appearance.
At the end of the eighteenth century the production of such varieties came to a halt, stopped by the introduction of the China roses which flowered repeatedly, a new and popular feature. While R. chinensis itself is a weak plant, by hybridising, a remarkable number of varieties have been produced; for example Hermosa which never stops flowering. The portlands have also been produced from China roses, one of the best being Jacques Cartier.
A group of roses called the Bourbons came from natural hybridisation between the old blush China and the autumn damask on the Ile de Bourbon in the Mauritus group. One seedling which flowered repeatedly was brought back to France and itself hybridised, to produce the group called the Bourbons and the start of the modern rose. Bourbons tend to have poor garden value and are prone to disease, but there are some good ones, e.g. Boule de Neige .
The tea roses grow well in warmer climates but not in Britain where they are weak. Hybrids of these with hybrid perpetuals gave the hybrid tea roses, the first one being produced in 1869. They were not at the start at all satisfactory, and it took a long time to develop anything worthwhile. The object was to produce a high centred flower, unlike the old roses, and with a much greater range of colour, particularly yellow.
The next step was the floribunda rose produced by crossing hybrid teas with the polyantha rose, coming from R. multiflora. They had an abundance of flowers, but blooms of no value or scent. This is where the story becomes particularly interesting with the arrival of the modern English rose combining the beautiful flower, the charm of the rose, the fragrance, repeat flowering capacity as well as a good colour range. They have been developed over a number of decades, so that there are now very many good varieties available to gardeners.
The lecturer described, with nearly forty slides, examples of roses from all periods to illustrate this history, before explaining how hybridising is done, starting with the natural work of bees, and how in the 17th and 18th centuries pollen was transferred by hand.
Toward the end of the 19th century, Bennett, who was an English cattle breeder, saw what was being done in France in hybridising roses. He then applied his breeding methods to roses and soon showed impressive results. He also grew roses under glass to develop good hips for seeds, a practice still employed in large-scale commercial hybridisation today where the pollen is collected from the flower before it bursts from the stamens. The petals are stripped off and the pollen, collected in glass jars, stored in ovens at 20°C overnight and then applied to another stamen. Seeds are sowed individually and give about 20% germination. Plants are at first selected by their flower, about 1% being planted out in the field, where they are further selected for other desired all-round characteristics. One such, disease resistance, tends unfortunately to lead to rather boring plants. Insertion of genes into rose material has yet proved difficult, so breeding is still done by cross-fertilisation. The blue rose is probably some way off.
In answers to questions, we were told that there are hundreds of compounds in the scent of a rose; the type of soil may affect the perfume as well as the growth. Roses have a great range of different fragrances; one breeder is trying to produce, from R. gallica, a rose with scented leaves. ‘Sports’, he said, are encouraged by stress in the plant.
He recommended, for a small garden, the crimson English rose Noble Antony as having all the normally desired qualities. A new rose should not be planted where another had grown without replacing or sterilising the soil to the extent of a two-foot cube.
John Coates