Yes, indeed! You should find that Sempervivum species do better with a rock mulch, rather than wood. There is no need for all that moisture conservation, especially in your climate. Rock and sand will also make it easier to pull out weeds. let your Hen and Chicks grow tightly congested, and you may find that any weeds that find there way up through them will be pinched by the Hen and Chicks foliage as it grows, and partially pulling the weed seedling out of the soil. These are surprisingly easy to pull, as often they are holding on for dear life with a few single threads of root!

Rick

Weeds have made my tiny rock garden the most labor intensive little area in the garden, other than the Summer vegetables.
3 years ago I lifted and potted up any valued plants. Used weed killer to kill all that was left. Bought new rocks and arranged them all as naturally as I could and put plants back. Weeding every couple of weeks, at least, or any time I think of it. But some plants spread and help crowd weeds out.
Some of them tend to act like weeds, themselves.

I use burlap bags under the mulch/sand or rock/stones.
It helps with any thing that come out of the soil.
The wind & birds are another matter.

You have basically answered your question. In your perennial garden you have a lot of plants that keep the weeds in check. It is the same in a succulent garden.

Start with sedum as a ground cover. Then you add your rocks semps and other rock garden plants.

Here is my garden... Notice he amount of rocks and the plantings are in pockets. Weeds do not grow on rocks. The planting pockets are stuffed with plants so you do not get weeds just as a stuffed perennial garden have few weeds.
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