In winter evergreens and topiary come into their own. While in summer they might form architectural accents in lush herbaceous foliage, in winter they provide the main interest. Any border should be punctuated by repeat topiary shapes - simple geometric forms - balls pyramids, cubes - are the best. In winter their form is fully revealed and brings an otherwise empty bed to sculptural life.
Its always interesting to vary the colour and texture of evergreens so that even topiarised they have a pleasing contrast. Low winter sun also helps accentuate form and texture. Good clippable evergreens of varying texture and colour include holly (there are good varieties ranging for dark green blue, Ilex x meservae :”Blue Prince”, to silver and gold variegated varieties, Ilex aquifolium “Silver Queen”, and Ilex alterclarensis “Golden King”). In winter nothing is more charming than the berries that holly offers in colours varying from yellow to green and red.
In contrast Box gives a smooth texture of bright green throughout the year. The larger and coarser leaves of the laurels, Prunus lusitanica and Prunus laurocerasus, for instance, make a larger-scale shape and are particularly adapted to making clear stem standards with round mop-heads. The evergreen oak (Quercus ilex) though of Mediterranean origin does extremely well in Britain and makes a fine large clipped subject of a dark blackish green that contrasts beautifully with the lighter green of grass. At home I have a pair of these 4m high with heads 3m across - they form a frame to the entrance of the house.
A much underrated evergreen is the common ivy (Hedera helix) which clipped makes an excellent ground cover especially in dry and shaded places where grass will not grow. It can also be trained on frames to make simple shapes - a ring of wire in a pot, for instance, makes a charming growing wreath of ivy. They look particularly well in groups of 2, 4 or more on staging. Smaller named varieties such as Hedera helix “Ivalace” , might be better for this.
A less formal evergreen, Winter box (Sarcococca humilis) comes into its own in the winter as it has highly scented white flowers in January and February. It makes a very good low bed edging in a shady place. Though lax in form compared with box judicious pruning can make a tidy rounded low hedge or edging. Placed near a door or window it gives a delicious and highly unexpected scent at a time of year when you least expect it.
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