Christine Schmitz is a PhD candidate working on management models for fruit growers with the Horticultural Sciences team at the University of Bonn and the Dienstleistungszentrum Ländlicher Raum Rheinpfalz (Germany). Spring frost damage is a major problem for temperate fruit production in Germany. Techniques to protect apricot orchards against such damage include wind machines, paraffin candles and below-canopy irrigation. Christine implemented a decision analysis model to compare the costs, benefits and risks of different frost protection measures and production without frost protection in a probabilistic way to estimate their financial performance (as net present value (NPV)) over ten years. Assuming an established apricot orchard planted in southwestern Germany, the chance of obtaining a positive NPV without frost protection was greater than 90%. Similarly good results were projected for an investment in mobile or stationary wind machines, with an estimated chance of 88% for a positive outcome. The use of paraffin candles, which requires a high workload and high uncertainty regarding their efficiency, was found to be the least profitable option, with a chance of only 57% for positive outcomes. These results clearly demonstrate which frost protection measures are the best when considering the NPV. However, growers are also interested in stable and reliable yields over the years, leading towards a preference for stationary wind machines that combine good NPV with reduced yield losses. Further research will concentrate on the full orchard lifetime and on other species.
Christine Schmitz won the ISHS Young Minds Award for the best oral presentation at the International Symposium on Models for Plant Growth, Environments, Farm Management in Orchards and Protected Cultivation (HorchiModel2023) in Spain in June 2023.
Christine Schmitz, Dienstleistungszentrum Ländlicher Raum Rheinpfalz, Rheinbach, Germany, and INRES – Horticultural Sciences, University of Bonn, Germany, e-mail: christine.schmitz@dlr.rlp.de
The article is available in Chronica Horticulturae