One needs to be very careful when using rocks for ground cover in your kitchen gardener.
There is a need to replace water sucking lawn in unused areas. However, consider other types of ground cover such as drought tolerant shrubs, ornamental grasses,etc.
Just like pavement and sidewalks, rocks will absorb and reflect a tremendous amount of heat, making it hotter in adjacent buildings and homes as well as stressing any plants planted in them unless they are dry heat lovers such as sagebrush and lavender. It is also hard to clean fallen plant debris out of rocks and to weed out of them when the inevitable weeds begin growing. The kitchen gardener of course will be wise to this fact.
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