Theoretical computations of Rydberg energy levels series and atomic lifetimes for singly ionized boron (B II), silicon (Si II), and germanium (Ge II) have been performed. In the theoretical computation weakest bound electron potential model theory (WBEPMT) is employed. Regularities of changes in quantum defects for the following Rydberg states series: 2sns(1S0), 2snp (3Po0), 2snf(3Fo2,3Fo3,3Fo4), 2snf(1Fo3) of B II; 3s2ns(2S1/2), 3s2nd(2D3/2,5/2), 3s2nf(2 o F5/2,7/2), 3s2ng(2G7/2,9/2) of Si II; and 4s2nf(2Fo5/2), 4s2nf(2Fo7/2), 4s2ng(2G7/2,9/2) of Ge II, up to n = 50 are presented. The atomic lifetimes of the following series: 1s22sns(1S0), 1s22snp(3Po1), 1s22snd (1D2) of B II; 3s2ns(2S1/2), 3s2nf(2 o F5/2,7/2) of Si II; and 4s2ns(2S1/2) of Ge II are predicted with good accuracy. Some high-lying Rydberg energy levels and atomic lifetimes have been presented for the first time. The series for which Rydberg energy levels are computed in this work are unperturbed series.