Caring for trees in summer
The gardening spotlight traditionally turns to trees during spring and autumn. But this time of year is a great chance to see trees in their summer outfits so you can assess the eventual scale of your specimen. While you can ring the changes with bulbs, annuals and even perennials, it is crucial to choose the right tree first go: they are important features in any garden and particularly predominant in small spaces. Some arboretums include planting dates on the labels, which is immensely helpful if you are trying to ascertain whether this is the tree for you. Height, spread and rate of growth are demonstrated so much better than vital statistics on a website.
I am lucky here at Glebe Cottage in being able to borrow a tree-filled backdrop. On our scant acre I have probably planted too many trees. It is a bad habit. When I lived in London, our tiny, temporary Ladbroke Grove garden contained at least 10 trees. Fortunately I moved before they had a chance to settle in and form the first North Kensington forest, and I carefully lifted each one and sent it to a loving home.
Apart from two copper beech and an underestimated Prunus padus (bird cherry), most of the trees planted at Glebe Cottage are on the small, slow-growing side and many of them have much to commend them during the summer. The one that holds sway at the moment is Cornus controversa'Variegata' with spreading tiers of growth lit by its glorious cream and glaucous-green leaves. Its spreading, horizontal branches are arranged symmetrically around a central trunk, cantilevered and seemingly defying gravity. My tree has blossomed this year, so there may be blue-black fruit to follow, but the main attraction is its striking architecture and the brilliance of its foliage. It is a beacon in the midst of the garden, particularly uplifting in a gloomy British summer. It was lovely, too, in spring, its polished mahogany twigs adorned with pointed red-lacquered buds that unfurled almost overnight into illuminated shoots. Eventually this cornus makes a tree that would demand centre stage in a small garden; if space is at a premium, C. alternifolia 'Argentea' (or 'Variegata') is a doppelganger on a smaller scale.
The Katsura tree, C. japonicum, is probably my favourite tree; I've planted several. But katsura can become big, spreading trees, so in an attempt to curb my enthusiasm, yet still indulge my passion for them, we put in the elegant weeping form, Cercidiphyllum japonicum f. pendulum, as one of several small trees framing the cornus. Its waterfall branches clothed in heart-shaped leaves trail down to the ground. You can walk through it where the branches on its north side form a natural arch over the path.
As with many pendulous trees, occasionally a branch dies for no apparent reason. Summer is a good time to prune out dead wood, as you can see clearly what needs to go. I use secateurs to prune back twiggy wood and a pruning saw where a bigger branch needs to be taken out, leaving a neat nub of wood protruding. At one time the horticultural wisdom was to cut flush with the trunk and paint the wound; now the advice is to leave a small protrusion so the tree can heal itself.
Another solution to my quandary over lack of space for trees was to plant a fastigiate form, C. japonicum 'Rotfuchs', with close, neat bronze leaves. But why plant one when two will do? A pair of these make sentries in my "red bed".
Japanese acers are popular trees for small gardens. My mum bought several (one each) after my daughters were born. They do well on our substantial, neutral soil. The one that shines is Acer palmatum 'Osakazuki', which has something to commend it in every season, though is lauded most for its crimson autumn colour. It is lush now, its palmate green leaves tinged with crimson. I carefully remove any dead twigs with long-handled loppers.
Beware planting acers in a wind tunnel. They need the protection of big-brother trees or the shelter of walls or hedges to do their glamorous best; not because they are sissies – they are as hard as nails when it comes to cold – but in their native habitat they grow under a lofty canopy of forest trees which protects their thin leaves from wind damage.