Hexagonal SiGe has been theoretically shown to feature a tunable direct bandgap in the range 0.4-0.8eV. We study arrays of site-selectively grown Si_(1-x)-Ge_x nanowires (NWs) grown using the crystal transfer method in which wurtzite GaP core NWs are used as template for SiGe growth. Our approach opens up routes towards photonic band-edge lasers using group-IV NWs. Low-temperature µPL studies of arrays of SiGe NW-arrays reveal strong emission at 0.395eV and linear power dependence for weak excitation levels (P_ex~0.01-1kW/cm^2). For P_ex>4kW/cm^2, a new peak emerges at 0.37eV with an intensity that increases according to ~(P_ex)^5, indicative of stimulated emission close to the photonic band-edge.