EFFECTS OF PRUNING PRACTICES ON EIGHT ROSE CULTIVARS GROWN OUTDOORS

A.J. Downer , A.D. Howell, J.F. Karlik
Roses are frequently planted in landscapes in California. Pruning severity has always been linked to flower production and flower quality in glasshouses, but there are few reports of landscape-based research. Therefore, a four-year field trial with more than 500 plants of eight rose cultivars was conducted. Four pruning treatments were imposed: unpruned, pruned to a height of 0.91 m and five primocanes, pruned to 0.46 m and four canes, and pruned to 0.15 m and three canes. Plant quality and stem length were moderately affected by pruning treatment. Number of flowers was greatest in unpruned roses. There were few differences in plant quality between intermediate pruning-severity treatments (0.91 and 0.46 m height). Severe pruning (0.15 m) resulted in significantly fewer flowers in most cultivars over the four-year study period. The most obvious response was due to differences in cultivars themselves.
Downer , A.J., Howell, A.D. and Karlik, J.F. (2015). EFFECTS OF PRUNING PRACTICES ON EIGHT ROSE CULTIVARS GROWN OUTDOORS. Acta Hortic. 1064, 253-258
DOI: 10.17660/ActaHortic.2015.1064.29
https://doi.org/10.17660/ActaHortic.2015.1064.29
Rosa, pruning, garden roses, outdoor flower production
English

Acta Horticulturae