One of the best med gdns is Beth Chatto's in Essex - think they've used pea shingle.
I designed & planted a gravel garden in Kent using local pea shingle (the rounded, buff-coloured 10mm stuff, not the crushed sharp-edged gravel) which looked good - see pic ...
Is there a local source of suitable material to you ? - would be cheaper to get direct from there as transport is a major expense (and polluting).
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