Best way to eliminate weeds in a flower bed covered in small rocks?

You can try hot boiling water but do not get it on anything else

Use Preen in the early spring. It will help eliminate some reseeding/regrowing from the weeds. You will probably have to keep spraying and pulling because unless you can treat the whole entire area with Round Up without killing any plants you are just going to have weeds in that area that keep reseeding themselves and growing.

I had the same problem near my pool. After years of trying everything else i have up on weeding. I removed the rocks and sprayed weed-be-gone on the area. Then I covered it with a weed barrier and replaced the rocks. It has been 2 years and no weeds.

After spraying again, cover the bed with plastic, leaving slits for your bushes. Clear plastic will let light in and create a greenhouse effect, so that won’t work. So it’s black or another solid, opaque color. With more effort, you can use a scoop to get the pebbles out of the bed, pull the weeds out by the roots, spray really well, lay down the plastic, replace the pebbles (and add more), and enjoy at least a season of no weeds. Except for the area you leave around the bushes, which should be easier to weed. Best wishes ☺️

Try straw then pebible over that