Birches to lift the spirit - by Sally Gregson Vita Sackville-West once urged her readers to “plant for your winter pleasure, when the months dishearten”. It’s a sound piece of advice from a very great gardener. If the structure, the evergreen planting, and those precious winter flowers are considered first, the summer works itself out.Sissinghurst is famous for its formal ‘garden rooms’ enclosed by tall, dark yew hedges which provide a framework and contrast for the summer planting. But structural elements need not be hedging, walls, or fences. Strong elements informally repeated through the garden are just as effective, be they rounded box balls; tall, perpendicular junipers; or silver birches positioned strategically to guide the eye through the landscape. Ghostly white birches in particular populate the space; they stride alongside you, shifting as they advance and retreat from view. And in winter the effect is especially powerful. Perhaps the most spectacular of silver birches is the wellknown Betula utilis var.jacquemontii. More correctly it is the pure white ‘Himalayan Birch’. Its bark has the texture of brittle parchment that peels off to reveal an underlay of soft bufforange. At maturity it’s as tall (9-15m. 30-50ft) as a silver birch (Betula pendula) and creates partial shade beneath that is ideal for some contrasting woodlanders such as blue scillas, Brunnera ‘Jack Frost’, or in acid soils, drifts of brilliant blue autumn gentians. On heavier soils the spectral white trunks would make a vivid contrast to the stems of red enamelled dogwoods (Cornus alba ‘Sibirica’).  It’s a waxy substance called betulin that causes the bark to be more or less white. In other species of birch the betulin is less strong and that results in quite differently coloured trunks. Himalayan Birches (Betula utilis) vary according to where they originate in the wild. Those from Nepal tend to have deep red and rich brown bark. Others from Sichuan, China are especially dark, almost chocolate black with just a few hints of red and occasionally overlaid with a betulin bloom. They would be dramatic under-planted with Hydrangea serrata with their bright red autumn foliage, or perhaps dwarf Japanese acers. And beneath those could be planted mounds of wintergreen epimediums with their coloured leaves and delicate spring flowers and rivers of ‘black grass’ (Ophiopogon planiscapus ‘Nigrescens’).The Chinese Red Birch (Betula albosinensis) is exceptionally and rather subtly beautiful. The trunk is light tan in places, pink in others. Patches of betulin overlay the ground colours like the bloom on a ripe plum. And in winter ribbons of orange bark peel off the trunk and catch the low sun like stained glass. The Stone Birch, or Erman’s Birch (Betula ermanii) originates in Japan and is larger than its cousins (12-18m, 40-60ft). It makes a dramatic specimen tree for a big garden with its orangepink trunk and white lenticels. They contrast brightly against the bark, almost merging in places and forming a ridged texture. In autumn the leaves become a dazzling orange that enriches the colour of the trunk and branches, and lights up the whole garden. The selection, B. ermanii ‘Mount Zao’ has a darker, more purple bark and the lenticels become more complex, forming very evocative patterns that capture the eye, and the camera.  The weeping form of the Silver Birch (Betula pendula ‘Tristis’) lends an altogether different mood to the garden. Its lower crown that falls to the ground like a twiggy waterfall creates more shade than others and obscures the trunk. But in winter it creates not just an interesting shape, but just the right conditions for battalions of grape hyacinths (Muscari) and crowds of pink and white cyclamen (Cyclamen hederifolium).But perhaps the most interesting change of form arises with the increasingly popular ‘multi-stemmed’ birches. These are pruned down as seedlings by the nurseryman to make them branch out from ground-level. Sally Gregson took these photographs at the National Collection of Birches, Stone Lane Gardens, Chagford, Devon |