Urban pruning residues constitute an underutilized source of lignocellulosic biomass, whose compositional heterogeneity may condition thermochemical conversion and the properties of biochar intended for energy applications. This study evaluated the physicochemical properties and energy performance of biochars obtained from leaves, branches, twigs, and their binary and ternary mixtures of pruning residues of Ficus benjamina L. Seven treatments were carbonized at 500 °C for 1 h under limited oxygen conditions. The biochars were characterized through proximate and elemental analysis, higher heating value (HHV), Fourier transform infrared spectroscopy (FTIR), atomic H/C and O/C ratios, and conversion and energy performance indicators. Mass yield ranged between 30.49 and 37.01%, and HHV ranged between 18.06 and 25.50 MJ/kg. The biochar obtained from the 50:50 mixture of branches and twigs (T3) presented the highest values of energy enrichment factor of 1.48 (EEF), energy yield of 47.95%, carbon densification factor of 1.52, calorific value improvement of 48.20%, combustibility index of 9.40 MJ/kg, and volatile ignitability of 23.51 MJ/kg. The biochar obtained from leaves (T7) achieved the highest mass yield but presented the lowest values of HHV, EEF, and energy yield, evidencing that a higher mass yield does not imply a higher energy recovery. FTIR and the H/C and O/C ratios evidenced the aromatization and condensation of the carbonaceous matrix, with loss of oxygenated functional groups. The proportion of leaves, branches, and twigs conditioned the physicochemical and energy properties of the biochars, evidencing differentiated profiles among treatments and their relevance for the thermochemical valorization of urban pruning residues.