We present a comprehensive study relating the magnetic properties to structural properties of Mn+-implanted Si1-xGex films as a function of Ge content (x=0–0.5). Ferromagnetic ordering with three critical temperatures, TB∼10–16 K, TC1∼650–780 K, and TC2∼825–860 K, are reported in this material system. Element specific x-ray absorption fine structure results show that the majority of the Mn ions are nonsubstitutional in all samples. The transmission-electron microscopy coupled with z contrast and chemical analysis reveals the presence of Mn-rich nanosized clusters including Mn4Si7 in Si-rich samples and Mn7Ge3 phases in Ge-rich samples. A composition transition occurred at x∼0.2–0.3, where we observe a change in bond lengths and defect structures. Additionally, an enhancement in magnetizations with an increase in both TB and TC1 as well as a conversion from n-type to p-type conduction are also detected.