Individual plants can also be highlighted, by adjusting a spotlight to emphasise an individual shrub or tree. The same technique also works on any feature you may want to highlight. At the same time, it draws the eye away from less attractive areas you. Recessed uplights and wall spotlights can be used to even wider effect.
If you cannot mount a light source conveniently near to the feature you have chosen to highlight is at some distance, try spotlighting it with narrow beam directional lamps.
Shadowing with garden lighting is great fun. If you shine a spotlight in front of a plant, the light shining through projects an enlarged shadow onto a wall behind. As well as highlighting the foliage or structure of the item being lit of course.
Another way to highlight a wall is to position a fitting close to the wall surface, and shine a light across it at an acute angle. The light source can be in the ground, or on the wall, where downlighters can also be used.