National collection of roses

Curator: Marta Monder, PhD

The Collection of the Botanical Garden was founded in 1998, and in 2008 acquired the status of a national collection assuming the name of the National Collection of Rose Cultivars. This is the largest collection of roses in the country and is important on a world scale in terms of diversity of cultivars and species. The presented species and cultivars show the diversity of the genus Rosa, from those well known thousands of years ago to the latest new breeds from all over the world. The presented roses are representatives of all the important groups in terms of cultivation (shrubs, pillars, floribundas, groundcovers, miniatures, tea hybrids, polyanthas, grandifloras) and almost all groups in terms of origin (bourbons, hybrid perpetuals, noisettes, hybrid teas, etc.). Those which were important in the history of breeding roses, including Polish breeding, are also collected. Shrubs are planted in the collection, taking into account not only their origin and belonging to specific groups but also colour and shape of flowers, type of growth, and other features relevant for use in practice. Historic roses represent more than 200 taxa. Historical roses are considered to be cultivated species and their cultivars produced until the end of World War II. These roses are an important part of the cultural heritage of humans and biodiversity in cultivation. These roses draw attention because of their strong fragrance and the particular shape of flowers. The most diverse group are shrub roses. There are species and varieties, many historical roses and modern cultivars. These roses are once-blooming or bloom in flushes throughout the season. The first flowers of this group of roses appear from the beginning of May, and the last before frost. They are attractive not only during the flowering period. Their ornaments are also stems, thorns, fruit and colouration of autumn leaves. A valuable group comprises David Austin English roses. They are distinguishable by the direction of breeding, designed to combine the features of old roses and modern. Fragrant flowers have a characteristic shape of old roses, with a wide range of colours, while other features are similar to those of modern roses. Most English roses repeat flowering very well. The pillar roses are botanically primitive climbers, without specialized organs for climbing, catching with the support of thorns only. Older cultivars can be divided into two groups – ramblers and climbers. The climber type of roses are derived mostly from the Wichura rose (Rosa wichuraiana) and Kordes rose (R. × kordesii). The rambler type of roses originated mainly from the multiflora rose (R. multiflora). 'New Dawn' (1930) is the first cultivar repeating flowering and the first plant protected by a US patent. The roses dedicated to the border belong to four sub-groups of roses: polyantha, polyantha hybrida, floribunda and grandiflora. These shrubs have abundant and long flowering, and are more resistant to disease and frost than Hybrid Teas. Their flowers amaze with their forms and rich scale of colours. Many of the new cultivars have pastel or amazing other colours of the flowers and are more resistant to diseases. Most of the new cultivars are easy to maintain.

The hybrid teas, hybrid perpetual, and teas represent a group of roses with a wide range of colours and different shapes of buds and flowers, with a nice fragrance. These are valuable cultivars bred a few decades ago as well as newer ones. The older cultivars of miniature roses are represented by more than 30 cultivars. They have small, pointed-form of flowers, small leaves, and include the Chinese roses and hybrid teas. New cultivars present great variability of forms and colours of flowers, and different types and vigour of growth.

The groundcover roses are intended for areas of extensive cultivation conditions, e.g. greenery, parks, along communication routes and pavements. They were classified as a group only in the 1970s. In this group there are several species, many cultivars already well known and new ones grown specifically for this purpose. Ground cover roses are characterized by a rich, long period of flowering, high resistance to cold and heat, diseases and pests, and they do not require a lot of maintenance work. Most of them bloom in flushes from June until frost.