Plant Diversity - The Rose

by Marketa Hermova 

When does plant diversity become a problem?

The Rose as a symbol of relationships, love and beauty has its historical roots in China, India, central Asia and Persia where garden hybrids were first cultivated. As the rose has become ever more popular over the centuries, propagation and breeding has brought thousands of different cultivars on to the international market, making choice difficult for garden enthusiasts. Gardeners are spoilt for choice and are at the same time covered in confusion, despite the fact that the modern classification of dividing roses into classes has brought regulation to assist these choices. Generally the gardening public considers colour, fragrance and scent well above how the plant is classified. The message from these gardeners to hybridists and promoters is that something new doesn’t automatically mean something better, unless that is, their breeding programme results in better colour, stronger scent, increased vigour and disease resistance.

Conversely classification is important to collectors who will always continue to acquire novelties, new introductions or recently discovered species, no matter their almost imperceptible differences or garden merit. These experts are concerned with the minutiae of cultivation, soil conditions, sunlight levels and annual temperature for example, rather than general effect. Rose breeders will always be driven to look for the ‘perfect rose’ that they believe will awake gardeners’ interest. But is their work appreciated by a public with broad and practical, rather than narrow and specific differences? Garden designers seeking to maintain good business relationships with their very often horticulturally-educated clients face the same issues. Should they promote vast choice over common garden excellence? Do their clients want to invest in collectables, when what they really want is colour and fragrance? Is it really necessary for designers to enter into long discussions with their clients and garden owners about plant nutrition, health requirements, periods of flowering, and the differences between ramblers and climbers, when all that is required is effect? Is it really then an advantage for the designer to have such a wide choice on which to base his proposal or does it only present difficulties in making the final decision? Without any doubt, novelties will interest the breeder, but will the new plant deliver as much satisfaction to the gardening public?

I read the other day an article in the Garden Design Magazine about research into the urban environment and city gardens. The research clearly shows that planting a wide range of different plants helps keep an area more environmentally friendly than planting just a few varieties often of the same plant. From the point of view of sustainability, the informed trend is to plant species and naturally occurring hybrids. Logically then, rather than planting a long list of difficult to grow exotics, it is must be preferable to plant species and their hybrids that historically do well in the local eco-climate.

Supporting this trend, contemporary gardeners are showing preference for planting species and varieties that are best suited to the naturally occurring topographical and climatic regime. Consequently Gallicas, Centifolias and Damasks have become popular with ecologically-aware city lovers or urban dwellers who miss the countryside so much that they imitate these rural environments in their city neighbourhoods. Looking at the benefits, such gardens don’t need as much maintenance, they are usually cost-effective and they bring butterflies and bees to the area while an owner is still enjoying the scent during the blooming period. The question is, do we really need hybridists to breed more cultivars if the high standards and attractiveness of our gardens is able to be simply maintained by growing our historic roses, those that we know do well in our environment? How many visitors to botanically orientated gardens in fact visit because of the valuable national collections and how many of them just want to spend a day outside surrounded by beautiful blooming plants?

The privately owned Evenley Wood Garden in Northamptonshire exemplifies the debate. Taking the advantage of wide range of soil types, collections of trees and shrubs were planted in the 60 acre with horticultural interest upper most in the mind of the owner. Over the last 30 years, the natural woodland has changed in character and roses have become part of that change. The recently established rose collection contains 120 different rose species and hybrids. You will not see a rose garden per se and you will not see beds of roses because that was never the intention. Instead the garden offers the chance to see ’Paul’s Himalayan Musk’ climbing to five metres or R. ’Belvedere’ growing to an impressive six metres. The double yellow-flowering R. banksiae lutea and the ‘The Garland’ with its cream-white flowers are displayed against the backdrop of the old woodland.Unsurprisingly, the network of paths edged with shrub roses that thread their way through the mature climbers and ramblers are one of the main attractions at Evenley during June and July. The Modern miniature remontant rambler R. ‘Warm Welcome’ extends the flowering season until September. Species roses include Rosa x dupontii, Rosa x longicuspis, Rosa x chinensis and R. moyesii which together with the ramblers R. helenae, R. ‘Blush Rambler’ and R. ‘Excelsa’ not only give colour to the summer but make the otherwise natural environment highly ornamental.

The majority of the plants planted at Evenley are hardy and even the R. ‘Lady Penzance’, the species R. davurica and climbing ‘Cecile Bruner’ have made good specimens. Not only is it the colour, some roses catch the visitor’s nose by their scent. R. ‘Dr. Eckener’ with its delight fragrance is one of the favourites. Another, the hybrid multiflora R.’Chevy Chase’ appeals to both senses with its strong fragrance and dark red colour. Those who benefit most from the flowering roses are pollinators. The shape and size of flowers of R. rugosa and R. canina are most suitable for the Evenley honeybees looking for a pink colour. Birds interested by red colours favour ‘Eddies’ Jewel’. Most of the climbers and ramblers have been planted singly, to climb or ramble up into trees and to impress. Shrub roses have been planted in groups of three alongside and to better define the paths. Evenley has also its own rose. The pink-flowering large shrub rose ‘Diana Miller’ is a ‘Betty Sherriff’ seedling that dominates its spot in the garden.

With the aim of supporting traditional rose cultivars, initially seventy cultivars from the Bred British Rose Collection are being planted in a relatively sheltered area measuring some sixty by forty metres. The area has been cleared of old ash and common hazel. The north facing slope, with its predominantly alkaline, well-drained and fertile soil and afternoon sun looks exactly right to meet the requirements of roses such as R. ‘Achievement’ and ’Climbing Christine’. Surrounded by conifers, the climbers ‘Awakening’ or ‘Blush Rambler’ will get natural support. ‘Captain Hayward’ which is a ‘Triomphe de l‘Expedition’ seedling needs less support, so will be grown as shrub close by. The vigorous ‘Kew Rambler’, a hybrid of R. soulieana x ‘Hiawatha’ will be planted during April. The thornless old Tea rose ’Mrs. Dudley Cross’, a pink-flowering R. woodsii fendleri and the yellow hybrid R. xanthina ‘Lindleyi’ will be planted at the same time.

The collection of roses bred in Britain comprises of varieties that are unavailable in commerce. In consequence it is hoped that the collection may become used as a source of genetic material for conservation and restoration projects. At the same time the collections have great potential as educational tools and to show fundamental principles of pruning and the other techniques.

With all due respect to new novelty cultivars, we shouldn’t forget to maintain those which have been grown historically. Most experts would agree that to find an appropriate balance between conservation and innovation is always difficult.

Marketa Hermova
Assistant Head Gardener, Evenley Wood Garden
KLC Open Learning Diploma Garden Design Student