The basics of the self-assembled growth of GaN nanorods on Si(lll) are reviewed. Morphology differences and optical properties are compared to those of GaN layers grown directly on Si(lll). The effects of the growth temperature on the In incorporation in self-assembled InGaN nanorods grown on Si(lll) is described. In addition, the inclusion of InGaN quantum disk structures into selfassembled GaN nanorods show clear confinement effects as a function of the quantum disk thickness. In order to overcome the properties dispersion and the intrinsic inhomogeneous nature of the self-assembled growth, the selective area growth of GaN nanorods on both, c-plane and a-plane GaN on sapphire templates, is addressed, with special emphasis on optical quality and morphology differences. The analysis of the optical emission from a single InGaN quantum disk is shown for both polar and non-polar nanorod orientations.