Giving gardens distinction

Press, 13 June 1986, Page 15

Giving gardens distinction

Shrubs and trees with presence:

Gardener’s B diary I Derrick Rooney

Some herbaceous plants — trilliums and hostas are among them —• have the ability by their very presence to give a garden a look which sets it aside from the ordinary and pedestrian. Some shrubs share this ability — among evergreens, some rhododendrons and camellias have what it takes; among the trees, magnolias. One of the most starkissed deciduous small trees is a distant cousin of the rhododendrons. This is Oxydendron arboreum, the "sorrel tree.” Slow growing, the sorrel

tree takes ages to make a large specimen and it would be unusual for a 1 fl-year-old to be taller than five metres. In England, where the sorrel tree has been grown since the eighteenth century, the tallest known specimen is only 19 metres. In New Zealand the sorrel tree is fairly rare, but it has been propagated by a Southland nursery and some stocks were available to Canterbury gardeners last year. One of the few mature specimens to be seen is in the woodland section of the Christchurch Botanic Gardens.

Long, glossy leaves, light green, give the sorrel tree an air of distinction in early summer, even before the long arching sprays of dangling, urn-shaped white flowers appear. Sometimes the floral display is prolonged until the leaves begin to change colour for autumn, replacing the green with scarlet and gold. Few trees hold their autumn leaf colour as well as does the sorrel tree, whose display can continue for many weeks. The sorrel tree comes from the eastern United States, where it is known

as the “sourwood.” Though it grows in the southern states, it is a tree of high elevations in the mountains and is thus fairly hardy. The sorrel tree isn’t just a pretty face. A Georgia Conservancy botanist described it as one of the world’s best bee trees. Sorrel tree honey doesn’t just taste good — sweet with a slightly acid aftertaste — it cures various ailments, too, according to the folk-medicine people. Mixed with an extract of wild cherry, it was handed out as a cough medicine. Mixed with moonshine whisky, it cured gastric disorders.

Red autumn leaves from the tree, powdered and mixed with “anvil dust,” made a dropsy medicine. They also yielded a black dye. The bark was put to use for dye and medicinal purposes. The wood made excellent sled runners, tool handles, and bedposts. All this and pretty with it! You couldn’t ask for much more of a garden tree. All the sorrel tree will ask of you is an acid soil, shelter from wind, and a little moisture in summer. It can be grown from cuttings. From the other side of the North American continent comes a distant relative of the sorrel tree which is equally distinguished as a small tree

for gardens. This is the Californian "manzanita” (Arctostaphylos manzanita), which is evergreen, has smallish, leathery, elliptical leaves, and hides them in its season with masses of little urnshaped, off-white flowers. In mild climates the manzanita flowers in winter. In cooler gardens its flower buds develop in autumn but do not open until spring. Neither the flowers nor the leaves is, however, the reason why the manzanita is grown in gardens. This is a tree which is highly prized for its bark — smooth, glossy, and mahogany red.

The smoothness is enhanced by the self-clean-ing ability of old trunks to shed naturally the stubs of dead twigs and small branches. Once a year, usually in midsummer, the old bark itself is shed, cracking and peeling to reveal new bark underneath, and for a few weeks the whole plant is gloriously tinted orange.

The manzanita has a reputation, fostered by overseas writers, for slow growth and for this reason is usually listed as a shrub in catalogues and gardening books.

I haven’t found it so. The specimen in my garden, planted early in 1981 to replace another that had been drowned in a 1978 flood, is already a dominant feature of the border in which it is growing. It is a good three metres high now and I have assisted the natural shedding process by clear-pruning the stems and thinning them out to above head height, so that the bark colour becomes even more a dominant feature of the plant.