I don;t know how, but my pine straw has really held well. The only things I've covered with buckets were my more tender roses, and I did have to put a brick on those.

Regina, Once it has been down a few days and has been rained on or watered with a hose or sprinkler, it sort of compacts and clumps together or sticks together.

When we mow weekly, I dump a thin layer of grass clippings on each garden bed and path straight from the mower's grass catcher. They are green and fresh. That first day, the weight of the fresh, green clippings helps hold them in place. As they dry, they stick to one another.

All bets are off if you're having 40-60 mph wind gusts. There's not much you can do to keep mulch from blowing in that sort of situation.

If you are in a very windy area, you could lay down bird netting on top of the mulch. That might hold it in place. It would be annoying to have to put it down though.

When I used hay or straw, I'm usually using aged hay or straw that is half-rotted already, and by half-rotted, what I mean is that it already is turning into compost. That helps it to hold together.

Fresh straw and fresh hay are sort of lightweight and do blow around easily. You can help prevent that by spraying them with water as soon as you put them down.

If you are in an area too windy to use hay, straw or grass clippings, then maybe you should use something else, but with strong wind, most mulch will blow away or wash away.

I constantly alternate layers of different kinds of mulch....hay, straw, grass clippings, chopped/shredded autumn leaves, leaf mold raked up from the woods, half-finished compost, etc. Using that sort of conglomeration of different mulches also seems to make all of them stick together better than any one single mulch does on its own. I don't know why.

Dawn