Summary:

Spring frost in the blooming time can be a significant factor decreasing the fruit production and affects the cultivation profitability in the years with unfavourable weather conditions. In Poland, the fruit trees especially susceptible to damage are peach and apricot trees. Among the popular methods of protecting the trees against spring frost damage there are three kinds of treatment: sprinkling irrigation, fogging, smoking and using fans for mixing the layers of air. The costs of applying the particular methods differ, as well as their efficiency. The side effect of using them can be also orchard pollution. The experiment was conducted on selected peach tree cultivars, on two rootstocks. Two methods of spring frost protection were applied: sprinkling irrigation and fogging with the use of glycerin mixed with tap water in proportion 1:10. Sprinkling irrigation proved to be more effective, it protected 98% of blooms. Using the fogging device also brought a satisfying effect. The cultivars that were easily damaged by spring frost were 'Early Redhaven' and 'Cresthaven'. The greatest resistance to bloom damage was observed in the case of the 'Suncrest' and 'Saturn' trees. The yielding of the 'Inka' and 'Early Redhaven' trees protected by sprinkling irrigation was significantly better, as compared with the fogged trees. The mean fruit weight was determined mainly by the cultivar.