A planting scheme will inevitably succeed if it is based around foliage.
When it comes to planting plans it is helpful to realise that for the most part foliage plays a more important role than flower. The shape, textures, heights and patterns of simple green leaves and stems is on show for the whole season, whereas flowers come and go.
Sticking to a simple pallet of greens, and resisting the urge to include coloured or variegated foliage can produce a calm and sophisticated design.
If the majority of the planting follows these rules, then a small amounts of a single colour — white, lime, yellow or cream for example — can be included judiciously with great success, for example, the Hosta in this planting with its bold cream variegation and white late-summer flowers.
Such restrained use of colour and flower can make the exceptions (such as the Hosta ) really take centre stage. In this regard I have found larger flowers, such as Iris, tulips, agapanthus, peony and foxglove to work far better than smaller, fussy flowers. A clear splash of colour surrounded on all sides by calm, textural green foliage simply cannot be beaten for impact and drama.
Scaly Male Fern
Dwarf Umbrella plant
Darmera peltata nana
Epimedium versicolor Sulphureum
Wavy Plantain Lily
Hosta undulata Mediovariagata