For some reason, I feel like have much better control with plot.xts function from the xtsExtra package described here over some of the other more refined R graphical packages. Maybe, it is just my simple mind, but recently I wanted to shade holding periods with points for buy and sale dates. With plot.xts from xtsExtra I was able to quickly and easily generate the following plot. I did have to slightly amend the original plot.xts function as seen here, but it seemed more natural and like much less of a struggle.
I also enjoyed writing this post almost entirely in R markdown.