Bolaina is a promising tree for the establishment of silvopastoral systems in Pucallpa, however, it has shown a low initial growth rate and highly variable establisnment vigor when planted in open fields. Local experience suggests that the establishment vigor of bolaina is affected by soil fertility. This study was conducted to identify which soil fertility component could best predict the variability in plant height and diameter one year after transplant. Three bolaina plantations provided 76 plants with a wide and uniform range in plant height and diameter. A composite soil sample was collected at 30 cm from the base of each plant at a depth of between 0-10 cm. Soil samples were analyzed for pH, OM, available P, and exchangeable Ca, Mg, K, and Al. By using the MAXR and STEPWISE model-selection methods it was found that Ca, and possibly Al and P were the best predictors of variability in plant height but had a low coefficient of multiple determination (R2=33% ). lndividually, Ca showed a linear and quadratic effect on plant height. lt is apparent that bolaina requires an adequately managed soil cation exchange complex for satisfactory establishment a year after transplant.