Relationship between Flower Yield, Flower Character and Weather Parameters as Influenced by NPK Fertilization in Super Star Roses

The quality and yield of “Super Star” rose flowers were influenced by climatic factors. Large sized flowers with many petals were produced in 15 to 21°C mean temperature, 55 to 80 per cent relative humidity and 5 to 8 hours sunshine. Maximum production of flowers was recorded in 21 to 31°C mean temperature, 60 to 80 per cent relative humidity and 6.5 to 8 hours sunshine. In such ranges, however, flower quality was reduced considerably. Addition of 75 g N, 125 g P₂O₅ and 100 g K₂O in soil per 1.44 sq.m. produced maximum number of flowers and more petals per flower in every month of the year. Flower petal number was influenced by temperature and humidity and was more during December to March.