This study was implemented to determine effectiveness of various treatments in recovering boron (B)-deficient olive trees in the Marmara region. The study was carried out during the period 2000-2005. The experimental soil was in loamy texture with medium alkaline pH, low organic matter, and low B concentration. The experiment was conducted in a randomized plot experimental design with 12 treatments. In the study, different B fertilizers were applied to soil and leaves. Treatments of 125, 250, and 500 g-1 borax (sodium tetraborate) were applied to the soils at the beginning of the experiment to determine the later effects of sodium tetraborate. Treatments of 125, 250, and 500 g borax were applied to the soils every year in March. Also, 0.4% borax was applied two or three times, 0.8% sodium tetraborate two or three times, and 0.5% bor-track (boron ethanol amine) two times by foliar applications during the growing period. According to the results, two applications of 0.4% sodium tetraborate to the leaves gave the best results. Soil applications of 250 g sodium tetraborate every year and 500 g sodium tetraborate every two years were the most effective treatments.