Flower Production Related to Re-blooming Time of Three Rosa hybrida Cultivars in Response to Rootstock Type

Abstract

Yield performance related to the time required for re-blooming after cutting of three Rosa hybrida cultivars (First Red, Versilia, and Virginia) was evaluated both on their own roots and grafted onto three rootstocks (Rosa indica, Rosa canina, and Rosa hybrida cv. Natal Briar) in a plastic house experiment for two successive years (1999 and 2000). Regardless of rootstock type, the three cultivar-rootstock combinations were superior (p<0.05) to the own rooted plants for yield and re-blooming time required. Irrespective of the cultivar, Natal Briar rootstock exhibited significantly higher flower production and spent a shorter time to re-bloom compared to the other rootstocks (R. indica and R. canina) and the rooted cuttings. Although, the later two rootstocks, R. indica and R. canina performed similarly, they were significantly better than the own rooted plants with respect to yield and re-bloom time. It is concluded that rose cut flower production is negatively correlated with the time (days) taken from planting to re-blooming. The shorter the time required for re-blooming the higher the flower yield, especially on the Natal Briar rootstock.