Birches Birch brings eye-catching bark colour and texture to winter gardens. Betula albosinensis ‘Bowling Green’ is one of many named selections. GAP PHOTOS / CAROLE DRAKE CAROLE / PHOTOS GAP CHOOSING THE BEST BIRCH Much loved for their graceful appearance, particularly in winter, Betula are fine garden trees with an appealing range of bark colours. Here are 12 good selections to consider Author: Hugh McAllister, leading authority on rowans and birches January 2014 | The Garden 57 Birches ew trees have as much winter impact as be multi-trunked) but, where there is space, they are also LENTICels birches – it is hard to think of any others with seen to advantage planted in groups of three or more so ON BIRChes Lenticels are Betula growing advice wintertide charms more impervious to cold the trunks diverge as they grow. This looks better than an markings on bark and wet. Their glorious bark, so often pristine ‘orchard-like’ planting of evenly spaced trees. made of porous ✤ Overview: birches are usually quick- other trees. As their usual grafting rootstock ✤ Maintenance: minimal; may benefit from white but also pink, copper, near-red or glossy cells that allow gases to pass growing, slender trees with decorative bark is shallow rooted, many herbaceous plants having their canopies lifted: see box, pp60–61. Fbrown, places them at the top of the pile, but most are Birches for the garden between layers of and appealing form, especially in winter. may struggle to do well below them, but ✤ Pests and diseases: older trees can be also of elegantly slender form. Birches are probably the The best known, and probably fastest growing, is Betula tissue. On birches spring bulbs and particularly cyclamen will ✤ Soil: not fussy – they grow in most soil susceptible to fungal attack; also birch rust thinnest-twigged, smallest-leaved of commonly grown pendula (silver birch) which occurs from the west of they appear as usually thrive. transverse types, acid or alkaline, and even tolerate and birch leaf mining sawfly may occasionally trees, giving lightness to their leafy crowns and delicacy Europe to eastern Asia and Japan. This is a short-lived tree, streaks, often in ground prone to occasional waterlogging. ✤ Water requirements: these trees like plenty cause problems. a contrasting to the tracery of their winter canopies. They are also its usefully attractive life probably in the range of 20–30 ✤ height to around 20m (66ft) by of water after planting but will withstand colour to the bark Size: ✤ Planting: birches do not transplant easily; beautiful in spring as their young leaves expand and the years in most areas; older trees develop corky trunks, shed some drought once established. and contributing 10m (33ft) across, but usually rather less. plant bare-root trees only when small. airy crowns are draped with catkins, while in autumn twigs and branches and can become infected by fungi. much to the ✤ Garden position: birches need plenty of ✤ Hardiness: most are exceptionally hardy to Pot-grown plants should establish easily as trees’ charm. most have golden yellow leaves. Most other species such as Betula utilis and B. ermanii light and are unsuitable for growing under H6 (-20°C / -4°F) or H7 (colder than -20°C / -4°F). long as they are well watered after planting. Birches are often grown as specimen trees (which can are slower growing and decorative in the garden for » RHS / TIM SANDALL TIM / RHS Betula pendula Betula utilis Betula utilis Betula ermanii Betula utilis Betula dahurica ‘Tristis’ ‘Bhutan Sienna’ var. jacquemontii ‘Grayswood Hill’ ‘Park Wood’ ✤ Mature size: H: 20m (66ft), S: 12m (40ft), usually less in UK cultivation. ✤ Mature size: height (H): 20m (66ft), ✤ Mature size: H: 15m (50ft), S: 10m (33ft). ✤ Mature size: H: 15m (50ft), S: 10m (33ft). ✤ Mature size: H: 15m (50ft), S: 10m (33ft). ‘Grayswood Ghost’ ✤ Foliage: rounded leaves to 7cm (3in) long, spread (S): 10m (33ft). ✤ Foliage: leaves up to 10cm (4in) long, ✤ Foliage: glossy, rich green leaves to 10cm ✤ Foliage: handsome, shiny leaves, ✤ Mature size: H: 15m (50ft), S: 10m (33ft). turning yellow in autumn. ✤ Foliage: leaves to 7cm (3in) long, blue-green glossy, dark green and deeply veined with (4in) long and wonderful, reliable golden yellow yellowish in autumn, to 10cm (4in) long. ✤ Foliage: large, glossy, rich green leaves to ✤ Bark: peels as small individual ‘curls’ with developing yellow tints in autumn. yellow autumnal tints. autumn leaf colours. ✤ Bark: attractive, smooth, peeling dark- 12cm (5in) long, often turning bright yellow a whitish outer surface, red-brown within. ✤ Bark: silvery-white and smooth to the base. ✤ Bark: bright red-brown, peeling freely. ✤ Bark: particularly beautiful: peeling creamy chocolate bark with contrasting large before falling. ✤ Habit and appeal: the ‘shaggy’ bark gives ✤ Habit and appeal: graceful, tall birch with ✤ Habit and appeal: fine birch with superb white, tinted orange with pinkish lenticels. whitish lenticels. ✤ Bark: among the whitest of all birches. a curious look, especially in winter sun. Deep weeping branches. Not for small gardens. bark and a lightly spreading crown. ✤ Habit and appeal: choice, strong-growing ✤ Habit and appeal: desirable tree forming ✤ Habit and appeal: a vigorous selection rooted and drought tolerant once established. ✤ Other comments: a good choice as a land- ✤ Other comments: collected by a Royal but slender tree, best in autumn and winter. a light canopy and has unusual bark colour. with dazzling white bark, best seen in winter. ✤ Other comments: introductions from Korea scape tree where there is space. Do not confuse Botanic Garden Edinburgh trip to Bhutan, ✤ Other comments: desirable tree with fine ✤ Other comments: probably derived from Leaf cover is quite dense in summer. and Japan do better in the UK than those of with lower-growing B. pendula ‘Youngii’, which where this reddish bark is a local charac- autumn tints and bark. Originating from a plant a collection by EH ‘Chinese’ Wilson in the ✤ Other comments: originates from a tree continental east-Asian origin. Cultivars ‘Maurice has a spreading rather than erect crown. teristic. Many Betula utilis are slower than of unknown origin at Grayswood Hill. Bark may early years of last century and grown at in the garden at Grayswood Hill, Haslemere, Foster’ and ‘Stone Farm’ were grown from Holds an RHS Award of Garden Merit (AGM). B. pendula and make smaller trees. take five years to colour well. Holds an AGM. Hergest Croft in Herefordshire. Surrey. Holds an AGM. Japanese seed by the late Kenneth Ashburner. 58 The Garden | January 2014 January 2014 | The Garden 59 Birches RHS / TIM SANDALL TIM / RHS Betula utilis Betula albosinensis Betula utilis Betula utilis Betula utilis Betula albosinensis ‘Forest Blush’ ‘China Rose’ ‘Nepalese Orange’ ‘Mount Luoji’ var. jacquemontii ‘Pink Champagne’ ✤ Mature size: H: 15m (50ft), S: 10m (33ft) ✤ Mature size: H: 10m (33ft), S: 8m (26ft). ✤ Mature size: H: 15m (50ft), S: 10m (33ft). ✤ Mature size: H: 15m (50ft), S: 10m (33ft). ‘Inverleith’ ✤ Mature size: H: 15m (50ft), S: 10m (33ft). ✤ Foliage: leaves are distinctively small and ✤ Foliage: rather delicate; oval and soft ✤ Foliage: glossy, rich green leaves to ✤ Foliage: glossy, rich green leaves to ✤ Foliage: delicate; oval and soft green to ✤ leathery to 10cm (4in) long. green to 7cm (3in) long. 12cm (5in) long. 12cm (5in) long. Mature size: H: 15m (50ft), S: 10m (33ft). 7cm (3in) long. ✤ ✤ Bark: beautiful and smooth, creamy, tinged ✤ Bark: attractive, coppery red and smooth ✤ Bark: copper coloured, peeling and marked ✤ Bark: rich coppery colour, peeling in scrolls Foliage: large, elliptic-ovate leaves to 12cm ✤ Bark: smooth, peeling and a beautiful with pink with well-marked lenticels. with little white bloom (powdery coating). attractively by lighter-coloured lenticels. with some bloom. (5in) create a dense canopy and have yellow pale pink colour, softened by a persistent ✤ Habit and appeal: ornamental selection of ✤ Habit and appeal: splendid, quick-growing ✤ Habit and appeal: attractive and unusual ✤ Habit and appeal: a good and choice autumn tints. Hairy young shoots. white bloom. ✤ slender stature and lightly spreading crown. red birch with lightly spreading crown. birch with a typical slender habit. ornamental tree featuring unusual rich bark Bark: smooth, striking creamy white. ✤ Habit and appeal: has paler bark than many ✤ ✤ Other comments: derived from George ✤ Other comments: a selected seedling from ✤ Other comments: a selection originally colour and producing slender growth. Habit and appeal: a popular, freely other so-called red birch, but a similarly slender Forrest’s collection number 19505, introduced seed sent by Chinese forestry authorities made by the late Kenneth Ashburner from ✤ Other comments: the original tree of this available selection. The bark begins to shape forming a lightly spreading crown. from Yunnan in southwest China in 1920 and from the province of Gansu, which gave rise a batch of seedlings he raised from seed fine selection is at Stone Lane Gardens in colour up well at smaller trunk diameters Quite a quick-growing tree. grown in the Royal Botanic Garden Edinburgh. to trees with a variety of bark colours. collected by Len Beer, Roy Lancaster and Devon and was grown from seed collected than most other birches. ✤ Other comments: an appealing selection ✤ Forrest described the bark of the wild tree as Several have since been named and Dave Morris in east Nepal in 1971. Not a by Lord Howick from Mt Luoji in Sichuan Other comments: probably identical to raised from the same batch of seedlings B. utilis var. jacquemontii ‘Silver Shadow’ ‘red’; trees in cultivation are paler. Holds an AGM. propagated. Holds an AGM. good tree for cold or exposed regions. province, China. as ‘China Rose’. More from the RHS longer, but some cultivars have denser, ‘heavier’ leaf canopies. Many For the top five trees » for winter bark: www.rhs.org.uk/plants birches with attractive bark have prominent lenticels (see note, p58).