Terrace talk - middle sized plants

Filling in the large areas between marker plants is a very enjoyable task - broad brushstrokes of texture and colour and - I hope - flowers. The types of plants are all rather ordinary: cistus, phlomis, senecio, abelia, lavender, helianthus. rosemary, artemesia and so on. But there are so many varieties of them that with any luck the final effect should be anything but boring. Cistus, for example, comes in different heights, spreading habits, leaf colours and textures and, of course, flower colours.
For a bit of variety there are also Raphiolepis and Ceanothus (repens), both of which have dark leaves to complement the predominance of silver plants.
I have tended to put groups of three of each type of plant in each spot as the main view of the terraces will be from across the other side of the lake and so clumps of plants are needed to make an effect.
I always plant in prime numbers: 1, 2, 3,5, 7 ... and especially avoid groups of 4. This is partly because the number four is considered unlucky (Chinese fung shui) but really because odd numbered groups have more 'movement'. The locals think I am mad but tempered their view when it was pointed out that Neapolitan tradition is that 4 is unlucky too.
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