this bit looks sparse but believe me it is chock full of plants, left of picture is cortaderia centre where the weedmat is showing is where I just lifted out a phoenix canariensis in a pot(just there for the winter to get more light, top middle is a small but covered in new shoots a magnolia(heaven scent) behind is a yucca

Pebbles are good.
Always like stones and boulders in gardens.:o)

One thing I can grow in my garden is stones, really only there to help hold down the weed suppressant, more than likely I'll put gravel on this in near future