This is an interesting photo because it shows a diverse range of colour in the garden without any flowers. This is an excellent way to design a garden because it provides year round interest. Flowers are then icing on the cake.

The colours in this garden shot also depend on the time of the day, the sun really brings to life some of the leaves and grasses.

The tall grasses also provide interest because of their swaying in the wind and gentle rustling sound.

Leaves of this Heuchera are now being bred in a range of colours and the textures that add additional variety.

Even in the vegetable garden you can grow some interesting colour schemes. These lettuce are just a couple of the varieties now available. I also like the ornamental cabbage giving colour throughout winter and the rows or savoy and purple cabbage can draw the eye.

Conifers are a bit passè but you can create some interesting effects with a bit of patience.

Bark can be black white or a multitude of colours in between. It often looks best in winter when it is not competing with as many shades of green.

Roots are not much to write home about but the ground can be coloured by nature as in this picture of autumn leaves.
Alternatively a nurtured but unnatural landscape of gravel, pebbles or chippings can colour the ground.