Observation Methods in the Clonal Selection of Herbaceous Perennials in Finland

At MTT Agrifood Research Finland, Horticulture, a project aiming at an increasing use of perennials in urban landscaping was started in 2005. To investigate the diversity of several perennial herbaceous plants in Finland, clones of several genera or species were collected from nurseries, and botanical and private gardens for field trials. The field trials were conducted in 2005-2010 in Piikkio and Espoo, Southern Finland and in Ruukki, Northern Finland. They consisted of 380 clones of Aconitum, Aconogonon, Asarum, Aster, Astilbe, Astrantia, Campanula glomerata, Delphinium elatum, Dicentra, Doronicum, Eupatorium, Fallopia, Geum coccineum, Hosta, Iris, Monarda didyma, Nepeta, Salvia and Thymus. The genera were selected because of their potential in landscaping and because of confusions in their nomenclature in the nurseries. The clonal selection of perennials aimed at finding the healthiest and hardiest clones for use in Finland and other northern areas, and for clarifying their nomenclature. The selection of the clones with the highest quality was done by intensive monitoring of health, pests, covering, growth, phenology, overwintering, flowering and ornamental value. On the basis of the results, about 10-15 new clones will be introduced into production, and renaming will be considered for about 45 clones in 7 genera. In this paper, the observation methods and their applicability are discussed.