re: Pine needles, hay, or cypress mulch?

I typically put pine straw in my beds out front, once a year. But I just have some large mature Holly plants up there. Every other year I lay it on pretty thick, and the next year it usually just needs topped off. It gets beat down with the wind and rain over time, and eventually breaks down back into the dirt. Smaller decorative stuff like perennials or annuals, I might shy away from it. But it is almost impossible to kill a Holly. I took a chainsaw to mine about a decade ago, down to the root, when they had gotten too big for me to easily keep them trimmed. Within a couple of years, they were about 3 feet tall again and skinny, but thriving. A couple more years and they had gotten thick again.