Mulching can present a dilemma for the novice in rock gardening. On the one hand, you want to suppress weeds in the rock garden, but, on the other hand, the widely used bark mulches would look out of place in rock gardens. So what do you use for a mulch?
The answer is stone. But not just any stone. Strive for a stone mulch whose color will fit with the color of your main rocks -- in my case, red. Fortunately, I had a range of sandstone rock at my disposal, from the large rocks that formed my circles to smaller stones to pebbles! The latter will make the perfect mulch for me. If I hadn't had such a supply on hand, I could have bought some red stone mulch from a local nursery (although the color wouldn't have been as perfect a match as I achieved).