Causes of variation in the price of roses

The flower auctions in the Netherlands play an important role in the price making process of cut roses. Growers want to know what the main quality aspects are which influence the price of their product throughout the year. One of the options they have, is to influence the stem weight by way of climate conditions. Growers consider that stem weight is very important. The quality of the supply on Flower Auction Aalsmeer of the cut rose 'First Red' has been monitored during the year 1997. Every four weeks a sample of six hundred roses originating from thirty nurseries (twenty roses per nursery) has been measured. The mean price per lot was obtained from the auction. A lot is defined as a number of containers with roses that are sold as one unit. Thirty features reflecting the visible quality of cut roses on the flower auction Aalsmeer (VBA) were measured. These data have been analysed by multiple linear regression and path analysis. From the results it can be concluded that besides stem length a few other product features also play a role in explaining price differences. Depending on the season the explanatory features were not always the same. Roses imported from Africa showed a completely different pattern of price influences compared to Dutch roses. Variation in flower bud diameter within a lot and the mean stem length of a lot appeared to have the most important influence on price differences of Dutch roses. Diameter and weight of flower buds are the most important features for the price of imported roses, in combination with some less important features.