Thaneshwari , B.S. Dilta2 and Y.C. Gupta
Abstract
The investigations entitled, Effect of nitrogen and potassium on growth and flowering of hydrangea (Hydrangea macrophylla Thunb.) was carried out at the experimental farm of Department of Floriculture and Landscape Architecture, Dr. Y. S. Parmar UHF, Nauni, Solan (H.P) during 2013 - 2014. The experiment was laid out in a Randomized Block Design (Factorial) with 5 levels of nitrogen i.e. N1, N2, N3, N4, N5 (40, 50, 60, 70, 80 g N/m2 respectively) and 4 levels of potassium i.e. K1, K2, K3, K4 (30, 40, 50, 60 g K/m2 respectively). Among different levels of nitrogen, N5 recorded maximum values for plant height, stem length, number of shoots per plant, stem thickness, number of leaves per plant, number of cut flowers per plant, and inflorescence diameter. However, minimum number of days taken to bud formation and harvesting was recorded with the lower level of nitrogen i.e. N1. As regards the effect of potassium, maximum plant height, stem length, number of shoots per plant, number of cut flowers per plant, and inflorescence diameter were recorded with the application of K3, and stem thickness was found to be maximum with the application of K4. The interaction, N5 × K3 i.e. 80 g N/m2 and 50 g K/m2 recorded maximum values in terms of most of the growth and flowering parameters of commercial importance. Hence, it is concluded that for better growth, flowering and yield of cut flowers, the hydrangea plants be fertilized with NPK @ 80:30:50 g/m2.