When we think of contemporary gardens we think modern, minimalistic, clean lines, lack of clutter. We often think of the garden complementing the indoor aesthetic, with a consistent design maintained throughout. The look is sleek, streamlined and sophisticated. You will need a simplified plant palate with shades of green.
The odd planter with either a complementary or contrasting colour arrangement should add a distinctive touch. There is an emphasis on architectural plants and repeat planting, maybe in straight lines, with box balls but with some prominent shrubs and flowers in white, silver or blue tones for interest.