If you can tell a lot about a gardener by what they plant I think you can tell a lot more by what they don’t plant. Most gardeners are impatient and that is why slow-burners do not sell as well as plants that give instant pleasure. How many times have we said, or thought, ‘I would like to plant one but they take so long to flower’. Of course, that is all the more reason to plant one NOW. I had some good sense to plant hedges and trees as early as I could in the new garden, even though trees need careful placement and I am already thinking that I have some in the wrong place as the garden design is evolving. I will stick with them though because the garden is so exposed and any protection is welcome and a little shade will be useful at this early stage in the garden’s development.
A shrub that is thoroughly useful and yet has not been included in my plant buying yet is Cotinus coggygria. And I am not sure why. It is hardly that it is unfamiliar or that I do not like it. In fact it was one of the first shrubs I ever knew. In my formative early teen years when we moved to the foot of the North Downs in Surrey, the garden contained a large purple cotinus, a small tree with a single trunk, that branched at about 1m off the ground and formed a big dome some 3m high and 4m across. It grew in thick, grey clay, over chalk, a soil that was a challenge to cultivate and make acceptable to most plants. I am sure the cultivar was ‘Royal Purple’ a deep but not very bright purple and distinguished by a thin red line round the leaf edge.
The cotinus was in old maturity and was a dark thundercloud of a plant all summer until it caught light in autumn, becoming a fiery orange and scarlet inferno, smouldering with its typical smoky old flower stems. It had character, colour and I was also enchanted by the sweet, resinous smell of its sap. Now I know that the sap can cause skin problems, being related to poison ivy, but it never bothered me.
So why have I not planted one yet. And why did I not plant one in the last garden, or the one before that?
I think that part of the reason is that garden centre plants look so unpromising, and so small. This is a plant for well drained soil and some small garden centre plants look rather overpotted and over watered. But that cannot be the reason why I walk on by. Perhaps it is because I was brought up with a huge specimen that I will never achieve in my own garden now that I am getting old?
Or perhaps it is because, as a student, I discovered, at Kew, its glorious relation C. obovatus, a bigger tree that has even better autumn colour. The two cotinus species are interesting for their disjunct distribution. Cotinus coggygria comes from southern Europe east into Asia and is sometimes called the Venetian sumach while C. obovatus is found wild only in a small area of Tennessee and Alabama and is very rare.
It is rarely for sale but, maybe for that reason I am holding out for it. In which case I should take advantage of the plant that Peter Dummer created that is a cross between the two species. Named ‘Grace’, after his daughter, this cotinus should be the one for me. It has larger leaves than C. coggygria and is full of hybrid vigour. It makes long shoots after a spring prune, clothed with pale purple leaves. Autumn colour is spectacular. This is not the only time cotinus have attracted the attention of hybridisers lately and there are several variations on the purple theme apart from the popular ‘Royal Purple’. Golden Spirit (‘Ancot’) is a beautiful, zingy lemon and lime creature but rather hard to place because it hates dryness at the roots and will show its displeasure with crispy brown leaf edges, and the rather creepily named ‘Little Lady’ is a compact, green-leaved cultivar with especially lovely pink-flushed flower clusters. Of course the flowers themselves are tiny but carried on delicately branched inflorescences that are covered in tiny hairs to create a wispy, smoky effect that leads to the common name of smoke bush.
Lots of flowers are only produced on plants that are infrequently pruned and left to grow naturally. And here again lies a dilemma. It is a popular practice to hard prune these plants in spring, to encourage strong leafy growth with the biggest, brightest leaves. I have seen ‘Grace’ treated like this many times. In this way it makes a good ‘back of the border’ plant to contrast with herbaceous plants or a ‘tropical’ mix of bananas, cannas, dahlias and ricinus. But regular pruning will shorten the life of cotinus. They are prone to coral spot fungus and making lots of pruning wounds and leaving stumps to die back only encourages the disease.
So am I going to buy one? Well of course. I seem to be planting a collection of autumn colour shrubs and trees at the west side of the garden. Apart from Euonymus alatus and three recently added liquidambars some Cornus alba ‘Sibirica’ are colouring up well at the moment and my tiny Acer griseum are making a little headway. The idea is that these will be illuminated by the setting sun when I sit in the conservatory with a G&T. Perhaps they need a cotinus for company. Like all gardeners I really am planning for the future.