Essential evergreens
Conifers must be the ultimate plant group for year-round appeal. Any weather, any season, almost any soil, they are there delivering the goods. There is such diversity among conifers; you can get even more visual value by planting species and varieties with unusually coloured leaves. It isn't just the benefit of what we see, it has been proven scientifically that the needles of conifers trap and neutralise those deadly disease-causing particulates, thereby improving air quality around our homes and workplaces. Harmful particulates adhere to the needles which eventually fall to the ground. They may then be washed away down drains and sewers or come into contact with soil where micro-organisms can detoxify the particulates.
Every garden needs structure, year round. Some plants deliver their goods in a rush - blossom on fruit trees, flowers on climbers or big blooms on rhodos - but evergreen conifers are constant. They offer instant impact - they will deliver from day one, no matter the season. It is this dependability that makes them a key building block in the design process, they really are a reference point with which to co-ordinate all other elements.
Style and fun are the key concepts to have in mind when thinking about conifers. Dwarf species, for example Pinus mugo are full of natural humour. Take ‘Mops' that almost spherical little tree that works so well in beds and borders, or Pinus pumila (Dwarf Siberian pine) - another star whose diminutive family member ‘Compacta' will happily slot in to most garden situations. These dwarfs need only a couple of metres of ground and will give so much year-round value in return.
Similarly, many of the golden conifers available in this country are dwarf varieties which make them highly adaptable for use in smaller gardens, or in areas of special interest such as rock gardens. In these situations they can provide colour and interest, especially when many other garden plants are dormant. The leaves of some take on a bronze tinge in winter which is an added colour bonus and all will look fabulous encrusted with hoar frost or dusted with a covering of snow.
Here are a few species and varieties that deserve a special mention. From the family of the White cedar, Thuja occidentalis ‘Rheingold' is highly valued for its golden-yellow foliage. An added colour feature includes the fact that foliage is pink-tinged when young and turns bronze in winter. ‘Rheingold' reaches a height of 1-2m. Another White cedar, ‘Golden Globe' has lots to offer as a plant for a rockery or small garden. A spherical, dwarf shrub, it has bright golden foliage and grows to an approximate height and spread of 1m.
If you're looking for a bigger tree with a columnar-conical form to fulfil a particular garden design theme, look out for Thuja plicata, it's an absolute beauty. From the family of the Japanese cedar (Cryptomeria) you can choose either end of the spectrum: ‘Elegans compacta' is an attractive conical shrub that has dark green juvenile foliage which turns bronze in winter and will reach 2-4m in height, whilst Cryptomeria japonica (Japanese Cedar) is a handsome tree that can reach 25m!
No survey of ever stylish conifers would be complete without a mention of Scots pine (Pinus sylvestris) ‘Gold Coin'. This slow growing shrub sports intense golden foliage and achieves a height and spread of approximately 2m.
Grow these conifers in deep soil with good drainage. They will do best in sheltered, sunny positions. Japanese cedars will tolerate chalky soils and are happy in partial shade. Thujas need shelter from cold drying winds.
Of the evergreens, Juniperus is an outstanding genus. With a range of between 50 and 60 species that includes prostrate shrubs to tall trees, there is a juniper for every situation, in rock gardens, borders, and as specimen plants. Juniperus squamata is popular in gardens because it can be a prostrate shrub, a spreading bush or a small upright tree (depending on variety). Many of these have gorgeous ‘glaucous' or blue-grey foliage that adds a further interesting dimension. Look out for ‘Blue Star', a compact bush that tends to reach maximum dimensions of 40cm in height and 1m in width. ‘Holger' has wonderful foliage effects, the new growth being sulphur yellow which contrasts with the steel-blue of the older leaves - height and spread of approximately 2m. ‘Meyeri' is different again, a larger shrub with arching branches and glaucous foliage, it reaches a height of between 4 and 10 metres and a width of up to 8m.
The common juniper (Juniper communis) presents some flexible choices, for example ‘Compressa', which reaches a maximum height of 80cm and is ideal for growing in a trough or pot. ‘Hibernica' is similar, in that it is another columnar shaped shrub, but bigger and faster growing than ‘Compressa' reaching a maximum height of 3-5m. ‘Grey Owl' is a low, spreading cultivar of Juniperus virginiana that is superb as a ground cover plant and will serve as a wonderful contrast with the seasonal colours of, for example, Cornus sanguinea ‘Winter Flame'.
Junipers combine well with other small conifers, heaths and heathers in a range of garden design styles. Low-growing shrubs like ‘Grey Owl' can even form the support for climbers such as perennial peas or delicate clematis.
Junipers are tolerant of many conditions and will thrive in quite hostile situations, such as hot, sunny sites or cold wet ones. Good drainage is certainly a help. Very little pruning, if any is required.
