Evergreens in strong, architectural shapes are the great fallback for winter, as well as providing year-round backbone to lighter-weight perennials. You don't need to buy anything extraordinary. The shape is the thing, and if it's not there, sharpen it up with some creative pruning.
Evergreen shrubs, for instance, don't need to have skirts to the ground. Raise them to expose some leg and you have an interesting, unidentifiable tree that will stay usefully compact. Mahonias and pyracantha become rather exotic when they have a parasol of leaves — and berries — atop a bare trunk that has been clipped of lower branches. As a bonus, you have created space beneath to plant spring-flowering bulbs and shade-loving woodlanders, such as hellebores and pulmonaria.
You can give architectural status to basic stockroom shrubs such as Choisya ternata or euonymus by shearing them over time into cushions, domes or globes, which gives them a presence that a more amorphous shape can't deliver. Arbutus unedo, the strawberry tree, makes a handsome evergreen and can be grown as a standard in ground or container; you can also expect a flurry of cream flowers and strawberry-like clusters of fruit when the weather warms. In a more formal space, a mature standard such as a lollipop bay or a red-stemmed Portuguese laurel, Prunus lusitanica, with a square-cut silhouette, makes a grand statement. Plant three on each side of a garden path, and suddenly you have an avenue. Or you could plant a lollipop version of Photinia fraseri Red Robin, a beauty which has glossy leaves and fresh new shoots in spring of a rich, vibrant red. Eminently clippable, it can also be bought as a shrub and given a sharp outline.
In recent years, the olive tree has become an evergreen staple in many town gardens, understandably replacing the deciduous silvery pear in popularity, and has proved its worth both in the border and in a pot. Contrast its shape and highlight the silvery leaves with a clipped green plinth of box or shrubby honeysuckle, Lonicera nitida.
Box is a risky bet now that box blight is so widespread. If it hits your patch, you might be able to save an established plant with some judicious cloud pruning. Light layers can be as rejuvenating as a great haircut.
For clippable substitutes, try phillyrea, euonymus, berberis as well as the cheery golden form of Lonicera nitida, Baggesen's Gold. Pittosporum tenuifolium Tom Thumb is a more novel choice. A bushy evergreen, it has dark stems with wavy leaves of a deep reddish-purple and makes handsome punctuation points at intervals along the edge of a border.
Plant winter sun stunners
Phormiums, with their long, swordlike leaves can be showstoppers, but avoid the dark, dour shades that will fade into the gloom, and choose brighter, lighter shades such as red and green Rainbow Queen, which looks stunning in winter sunlight. Astelia — the name evokes its steely foliage — creates a similar spiky outline. Variety Silver Spear is particularly sheeny.
Be creative, too, when considering how to clothe a wall with greenery. Ditch the ubiquitous ivy and instead, plant a silk tassel bush. Garrya elliptica James Roof is the underrated, upright-growing shrub that holds on to its dark green leaves and also produces long, silver-white catkins that turn a garden wall into a wonderfully decorative feature. And in the middle of winter, that's saying something.