Sources of Variability in Greenhouse Rose Flower Production1

Abstract

Abstract The flower yield of glasshouse roses is made up of 3 components: number of flowers appearing in the upper buds of the branches, number of flowering branches from the plant, and number of flowers appearing on ‘other’ parts of the plant. The number of flowers produced is the product of the number of buds sprouted times the percentage that flower. Flowering potential of the uppermost bud on a branch is greater and the rate of flower abortion (“blindness”) is less, than of buds produced lower on the branch Reduction in yield found during winter in cv. Baccara was mainly due to “blindness” of the uppermost bud. ‘Marimba’ was more productive than ‘Baccara’ due to a larger number of both flowers per branch and flowering branches per plant. The productivity of ‘Baccara’ when grafted on R. indica was greater than that of ungrafted plants because of the greater number of flowering branches produced on grafted plants.