Sorbus Vilmorinii

Two weeks of clear skies and cool nights have done wonders even for Britain’s autumn colours. It is worth planning for them when choosing trees and significant plants, and the options continue to multiply. New varieties turn up, sometimes from chance variations in nature, and nurserymen are alive to their potential. The best of them are more likely to go out in a bright blaze of coloured leaves.

On acid soils the family of liquidambars has always been at its best in autumn. These trees are famous for their production of a gum that oozes and hardens like amber, so much so that archaeologists have sometimes mistaken old chunks of it for amber in unusual contexts. Amber belonged especially in the Baltic north, whereas liquidambars are especially at home in southern Turkey and the north Syrian coast. In gardens their attractions are their prettily cut leaves, their upright habit and their autumn displays of red and red-brown colour. The drawback is that the best-known colourers have been slow to grow on in many British settings. Newer forms have now been selected and brought into the specialist trade. The old Lane Roberts variety has been the usual choice for gardeners but its dark red autumn colouring can look muddy even on a clear day. Much more impact is now available from the bright red Stella and the vivid Andrew Hewson, liquidambars worth tracking down in nursery lists. I have also been admiring the heavily cut leaves on a young Liquidambar Stared, a variety that colours a bright red on most soils even when it is still a young plant. All in all the liquidambars are no longer plants of variable impact that require a long time scale.

On any soil, acid or not, I always admire the good old Cockspur Thorn, Crataegus Crus-galli. Nobody is likely to be pricked by its spur-shaped thorns but their existence might be the reason why such a fine and robust tree has become less common in safety conscious city plantings. Gardeners should be less timorous, not least because this thorn tree is a great sight in autumn after months of glossy green leaf that reflects the sunlight very prettily. The Cockspur Thorn is a fine tree for lining out in a small avenue or along a boundary and is never troubled by disease. The only news here is that it is a perfectly safe choice, though its name worries rule-bound public planters.

At the Chelsea Flower Show this year I spent a while considering a welcome exhibit of new varieties of ginkgo. They now come in all shapes and sizes, including those with a low horizontal spread. At the end I was grateful to have planted only the usual Ginkgo Biloba in a site that has enough room for its eventual height and width. The newer ones are for those with less space to spare. It used to be impossible to buy the tall ginkgoes as anything more than small pot-grown specimens in the belief that they were difficult to transplant and establish. They are not but nurseries find them slow to reach a height of 6-8ft and therefore sell them earlier.

I can report on a ginkgo’s likely progress. In 1999 I ordered a 6ft Ginkgo Biloba from Landford Trees, Landford, Salisbury, Wiltshire, my regular source of excellent field-grown trees. During planting we knocked its leading shoot and did it no favours but this year, a decade later, it is a fine sight in full yellow autumn colour at a height of about 16ft. Allow 10 years, therefore, and you will not be disappointed.

If you happen to buy a female ginkgo you will eventually have to put up with its strong-smelling fruits, which are particularly vile when squashed underfoot. It might reassure you to know that they are the source of a highly praised aphrodisiac, said to improve sexual prowess by more than 70 per cent. The fruits do not appear for many years on female trees, by which time their planters might be grateful for this alternative medicine.

On limey soils excellent colour can be found in the family of sorbus. By now the merits of Sorbus Joseph Rock are well known: yellow-orange fruit, a relatively modest height, finely cut leaves and a brilliant range of autumn colours. The disease of fire blight is said to favour it but I seldom see or hear evidence of it. Last year I saw instead its upright clone, Autumn Spire, in equally robust health. New to me, Autumn Spire is a useful variation if you want a multi-talented sorbus in a restricted space. So is Sorbus Vilmorinii, a tree that can easily be contained at about 12ft but which is a lovely combination of finely cut leaves, pink-white berries and vivid autumn colour. It is healthy and high up among my choices as a small tree for an isolated position. In more generous settings the winner is Sorbus Sargentiana, usually the most brilliant colourer in the entire family. Its buds are a good deep red, too, enhancing the tree’s impact even before its leaves reappear in spring.

Gardeners on acid soils have the most options, ranging from brilliant acers to the vivid Nyssa Sylvatica. The rest of us can still rival them by finding room for one of the easiest of all small trees, the quick-growing Rhus Typhina, or Stag’s Horn Sumach. The curious name refers to the coating of brown velvet that runs along this plant’s stems as if they were a stag’s antlers. The spreading branches can be pruned hard in winter and kept to the dimensions of a medium-sized shrub. Alternatively, they can be left to develop a wide span and enough of a trunk to cast a light shade. Rhus Typhina grows on any soil and its cut-leaved form, Dissecta, is extra specially pretty. Has familiarity bred contempt for this brilliant flame-orange colourer? If so, look on it with new eyes, as it is still the equal of any fiery maple in the trade.