ggplot2 - Correctly arrange odd number of plots into one figure

Question

I have an odd number of plots to arrange into one figure and I desire to show the last plot centered in the last row of the figure.

Here some sample data:

Answer 1

A not-terribly elegant solution would be to leave the middle plot empty on the first row:

p_no_labels2<-list(p_no_labels[[1]],NULL,p_no_labels[[2]],NULL,p_no_labels[[3]])
p_grid = cowplot::plot_grid(plotlist = p_no_labels2, ncol = 3)