A combination of dense evergreen foliage and, in some cases, fine hairs on the leaves, can help to act as a buffer and filtration system for the garden.
For maximum filtering effect, the Taxus hedge creating the back row of this scheme should be allowed to reach a minimum of 2.5m in height and at least 1m in width.
The conifers and Cotoneaster have small leaves that are good for trapping particulate pollution such as smoke. Cotoneaster also makes good ground cover. Keeping the ground covered with plants helps to prevent unwanted seeds from growing, and protects the soil surface from erosion and moisture loss.
Until the plants have filled out, an organic mulch, preferably homemade compost, can help to lock in soil moisture and suppress weeds. Mulches should be spread when the soil is already moist to help trap some of that moisture before it dries out in summer.
1 - Taxus baccata ‘Semperaurea’ is an evergreen yew with dense golden-green foliage. The shrub has an orange tinge in winter and being a male variety, has no berries.
2 - Thuja occidentalis ‘Smaragd’ is a conical conifer that can provide an interesting focal point in a border with bright green foliage.
3 - Cotoneaster franchetii is an evergreen shrub with wide arching branches. Clusters of small white flowers in early summer, are followed by red berries.
4 - Elaeagnus pungens ‘Frederici’ is an evergreen shrub whose leaves are yellow centred with a dark green margin. Small fragrant flowers open in autumn.
5 - Pinus densiflora ‘Low Glow’ is a slow-growing dwarf conifer that forms a compact mound. It has bright green to yellow-green needles, with small cones.
6 - Stachys byzantina ‘Silver Carpet’ is a low-growing Perennials are plants that live for multiple years. They come in all shapes and sizes and fill our gardens with colourful flowers and ornamental foliage. Many are hardy and can survive outdoors all year round, while less hardy types need protection over winter. The term herbaceous perennial is used to describe long-lived plants without a permanent woody structure (they die back to ground level each autumn), distinguishing them from trees, shrubs and sub-shrubs.
7 - Erysimum ‘Bowles's Mauve’ is an evergreen perennial with dark grey-green leaves and a profusion of bright mauve flowers over spring and summer.
8 - Verbascum ‘Gainsborough’ is a short-lived perennial with tall spikes of primrose yellow flowers from a basal rosette of grey-green leaves.