EVALUATION OF LANDSCAPE ROSES FOR LOW-MAINTENANCE GARDENING

The morpho-phenological response of 59 landscape roses to a low maintenance regime without winter pruning, irrigation, fertilization and disease control was evaluated over a three-year period marked by hot and dry summers, a maximum temperature as high as 44°C for 5-10 days a year and 750 mm yearly rainfall, the latter usually concentrated in autumn.
Indices for cover (CI) and ornamental value (OVI) were established for commercial assessment of cultivars, especially chromatic impact of plant at peak flowering and ornamental blooming value from May to October, respectively.
At year 3 from planting, CI ranged from 0.16-2.40, the highest values being shown by ‘Alba Meidiland’, ‘Snow Storm’, ‘White Meidiland’ (white), ‘Bijou’ (yellow), ‘Doucer Normande’, ‘Ferdy’ (salmon-pink), ‘Rody’ (fuchsia), ‘Red Meidiland’, ‘Scarlet Meidiland’ (red) and most of the pink cultivars, i.e. ‘Bonica 91’, ‘Cumbaya’, ‘Lovely Fairy’, ‘Castore’, ‘Satina’, ‘The Fairy’, ‘Avance’ and ‘Altair’, whose total flower area almost doubled the canopy surface at maximum of flowering.
OVI rates ranged from 2.49-50.90, showing a long flowering period especially for ‘Doucer Normande’, ‘Bijou’, ‘Castore’ and ‘Alba Meidiland’. In xerogardening, we observe the spring peak to be always the most important season in terms of greater flower number, brighter colours and larger flower diameter.
Pruning omission induced an overly irregular canopy shape in several cultivars.

IV International Symposium on Rose Research and Cultivation

M.E. Giorgioni

ornamental value index, covering index, flowering, xerogardening

https://doi.org/10.17660/ActaHortic.2007.751.41