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Zinc sulphate and boric acid spray applications on, Shahroody 12, almond cultivars, in spring and fall seasons 1998-1999, were carried out in Horticulture Experiment Station of the Agricultural Faculty of Tehran University. The investigation was performed in a factorial randomized complete block design, in which three levels of zinc (0, 3000 and 5000 ppm) as well as boron (0, 1000 and 2000 ppm) were used as foliar application during bud formation in spring and after fruit harvest in autumn. Four healthy branches of 0.5m length were selected in each tree and the flower numbers recorded. One month later, at the end of flowering period and in June the fruit numbers on the same brancehs were recorded to determine the initial and final fruit set. During the next spring (1999), The same procedures for counting fruit set were repeated. The results showed that foliar application of 2000 ppm boric acid (in 1998) had significant effect on initial fruit set as compared to control, but in 1999 no significant effects on initial fruit setting were observed. The final fruit set in 1998 and
1 999 showed considerable increase due to boric acid application as compared to control. Zinc sulphate application had no significant effect on initial and
final fruit setting during years 1998-1999. The treatments caused a significant increase in leaf zinc and boron content.