A facile, cost-effective, and manufacturable method to produce gold-polymer nanocomposite plasmonic nanorod arrays in high-aspect-ratio nanoporous alumina templates is reported, where the formation of gold nanoparticles and the polymerization of a photosensitive polymer by ultraviolet light are simultaneously performed. Transverse mode coupling within a two-dimensional array of the nanocomposite rods results in a progression of resonant modes in the visible and infrared spectral regions when illuminated at normal incidence, a phenomenon previously observed in nanoarrays of solid gold rods in an alumina template. Finite element full-wave analysis in a three-dimensional computational domain confirms our hypothesis that nanoparticles, arranged in a columnar structure, will show a response similar to that of solid gold rods. These studies demonstrate a new simple method of plasmonic nanoarray fabrication, apparently obviating the need for a cumbersome electrochemical process to grow nanoarrays.