Notable Trees in Dulwich - Tilia henryana: Henry's Lime
This rare member of the Lime (Linden) tree family was found in central China in 1888 by the plantsman Augustine Henry, and is therefore often called 'Henry's Lime'; it was not introduced to Europe and the West until 1901, by the famous plant collector Ernest H. Wilson.
Limes are a member of the Malvaceae or Mallow family, and in Germany particularly, they are associated with the ancient goddess Freya and therefore denote love, spring, and fertility. There are many species of Lime, the most common in the UK being Tilia Cordata, or Common Lime, which grows larger and faster, and can be associated with coppicing, as it can cope with much pruning.
In contrast, Henry's Lime grows more slowly than most limes, and reaches 12 - 25 metres (40 - 82 feet) depending on position and conditions, in about 50 years, and thus requires low maintenance, although a slight tendency for sports on the trunk are best kept in check. These hardy and deciduous trees will generally be larger in the wild, than in cultivation, and have a spreading shape, of about 7 to 9 metres (approx. 25 feet) with a rounded top. The branches are reddish brown, and their buds are ovate and dark red. Young trees have a rather smooth bark, but older specimens (as with humans!) will become more furrowed.
This tree can cope with full sun or partial shade, so that planting positions are not a problem, and is amenable to any aspect of the compass: persistent severe wind would be unsuitable, however. The soil for a Henry's Lime needs to be moist but well drained, and planting in an alkaline soil is favourable, and although it can tolerate sandy and chalky conditions up to a point, it does therefore prefer loam or clay.
The foliage of the Henry's Lime is unusual and interesting, and arguably the most attractive feature; the leaves are much larger than most lime, being about 13 cm (over 5 inches) long. They are broadly cordate (heart-shaped) with both upper and lower surfaces being downy, and are edged with bristle-like 'teeth', or 'eye-lashes' of about 1 cm (approx. half an inch) each. These leaves emerge with a reddish tinge to them, and the colouring alters gradually over the summer, mostly turning glossy and green. Interestingly a second flush of foliage often occurs later in summer, and these leaves frequently have an attractive silvery pinkish-blue tinge; then, during autumn all the leaves turn yellowy gold.
Although most lime are the bane of car owners, owing to the sticky sap which drips from the leaves, the Henry's Lime is less prone to do this, but as with other limes, there is a tendency to harbour aphids, caterpillars and gall-mites, and be somewhat liable to diseases such as phytophthora and honey fungus attack.
One delightful and positive inclination is the tree's attraction for bees, though sometimes bees have been observed to become 'drunk' on the flowers, falling to the ground in a stupor. These flowers appear in late summer and are hanging clusters of around twenty-five creamy-white cup-shaped tiny blooms with a glorious and intense sweet and lemony fragrance, which incidentally, has long inspired poets, possibly the best example known being Boris Pasternak.
The fruit which forms from the flowers remains on the tree until at least late October, depending on climate, and are nut-like and pea-sized with wings, to aid natural dispersal.
Look out for a recently planted example which can be found in Dulwich Park, near the College Road entrance about 25 yards in, on the right-hand side.