Sage Advice

An exercise in patience

Callum Halstead

This month we’re reaching peak time for plant procurement. The Chelsea Flower Show is just weeks away and even those of us who, in fear of frost and other foul weather, may have been reluctant to get out into the garden throughout the early spring, are now emerging full of vim and renewed enthusiasm for another season of gardening. For the nurseries and garden centres, it’s boom time. Behind the scenes, teams of growers are working at maximum capacity, preparing masses of greenery to dress stands at the bigname garden shows, in the hope of securing coveted gold medals. Meanwhile, it’s also business as usual— meaning numerous busy garden designers to supply, countless orders to fulfil, and a steady stream of customers arriving on site in search of something stunning to take away with them. The people must have plants!

There’s a myriad of plants that are perfect for planting at this time of year, so you’ll have to forgive me for writing about ones that you can’t have now, or at least not yet— I’ll tell you why later on. The plants in question are trees. I’ve been thinking a lot about structural planting lately, and particularly about the general lack of it in many of our own gardens. My musings on the subject were prompted by the loss of four mature trees from the walled garden at Cambo Gardens, where I work, following Storm Arwen late last year. Historically, the walled garden was predominantly a productive space, and one of the trees lost was a fine old Bramley Apple (Malus domestica ‘Bramley’), likely planted around a hundred years ago or more. It is only in recent times that the garden has seen a change of use, and more ornamental trees were introduced. For this reason, wellestablished trees were still in the minority in what was otherwise quite an open space; however, the effect that these few specimens had on the feel of the garden was considerable.

Trees and larger shrubs lend a sense of maturity to a planting, and this can be so even when they are still relatively young. They can be used to give privacy and shelter to an area, providing sanctuary for both you and your garden’s wildlife. They are also highly effective at creating different moods within the spaces in which they are used, depending on the variety selected and how they are positioned. For example, trees with a more rigid structure and upright habit can be used to increase formality, while those with a looser crown and spreading habit can be used to amplify feelings of relaxation. Another of the trees that we lost to Storm Arwen was a Corkscrew Willow (Salix matsudana ‘Tortusa’), possibly one of the most relaxed trees there is, with its pendulous veil or twisting stems, and its fresh, green, sickle-shaped leaves. The change in the garden following the loss of these trees was stark. The filtered light that had danced on the flowers of the woodland bulbs growing below, was replaced by direct sunlight— also nice, but lacking motion and ethereal ambience. The mood and feel of the area fell, quite literally, flat. Gone was the mystery and intrigue about what was around the next corner, as you could see everything in front of you. Gone, too, was a sizeable amount of habitat for our resident birds, insects, lichens, and mosses.

These lost trees will surely be replaced— a wonderful thing about working in gardens is being able to witness and be a part of the renewal and regeneration after the drastic effects of a storm —and my colleagues and I have, in fact, already planted an informal avenue of white-flowering Crab Apples (Malus ‘Evereste’) in the walled garden to reinject some structure into the planting. But, for those of us without trees in our own gardens— myself included —and those who have never grown them, I suggest that we are all missing out on the wealth of potential diversity and interest that they create.

Whether you have booked tickets to go to a flower show this spring, or instead will be avidly catching up on the show’s highlights on TV, you are sure to see gardens that contain fine, well-structured planting. By this, I mean gardens that have distinct layers to them, with upper layers formed using trees and larger shrubs, bringing balance to the design and giving the impression that they have been growing in-situ for years rather than merely a few weeks. Many gardeners today seem almost scared to plant anything that might be in danger of growing above the fence line. My advice to you all is to be brave.

I particularly offer my encouragement to anyone who has found themselves living in a new build, where the words ‘structure’ and ‘garden’ can rarely be used in the same sentence— unless the structure in question is a barbeque house. New housing developments often stand out for their lack of mature or even young trees. You may have quite a job on your hands to add layers of interest to the planting, and often-times you won’t be helped by the poor quality of the soil that you find. At least at this stage, you have a blank canvas to do with whatever you so wish, and soil can always be improved. I appreciate that gardens are generally getting smaller, and that you may only have room for one or two trees at most; this is all the more reason to select a variety or two that will really earn their keep. Trees in a garden do not have to mean ‘deep shade’ for you and your neighbours. A good nursery or garden centre will be able to advise you on how large and dense a canopy to expect from any given variety, and will surely be able to recommend a tree that will be best suited to your requirements. You can also play with how much shade you create by altering how closely you plant them. Just remember that they will get bigger— it’s easy to forget —and space them accordingly. A spacing that may initially seem to be too far apart when the trees are young, will make much more sense once they have matured. This also applies when it comes to planting near buildings and walls. Give your trees the space they need to grow well.

May is certainly a good time of year to plan the addition of trees to your garden. Spring has well and truly sprung, and many of the best garden trees will now be finely dressed in their new season’s foliage. If you can’t get to a show, then a bit of internet research certainly won’t go amiss, but it won’t beat actually seeing plants ‘in the flesh’ or, perhaps, ‘in leaf’. While you are on the hunt for ideas, a finely crafted ‘trees and shrubs’ board on Pinterest can be very useful for saving your ideas and providing a visual reminder, but a far better way to understand which plants could work well in the space that you have available, is to see fully established specimens growing in another garden. Take inspiration from local historic and botanic gardens, or alternatively visit one or two of the magnificent private gardens that open their doors to visitors as part of the National Garden Scheme and Scotland’s Garden Scheme. At many public and private gardens that are open to the public, you will most likely also be able to find a helpful gardener, whose knowledge and expertise you can plunder for plant recommendations and growing advice.

Once you have made a note of some varieties that appeal and that you feel will be right for your garden, pause for a moment. I’m afraid that I am now going to make you wait. Rather than travelling straight to your nearest plant nursery and threading the finest specimen tree that you can find through the gap between the back seats of your car, consider instead phoning up and placing an order for delivery in the autumn. In a culture where the mantra ‘everything now’ generally prevails, I appreciate that exercising restraint and having a bit of patience can be a tough ask, but there is good reason to bide your time. These plants could well be some of the most valuable plants you will put in your garden, so to ensure that you get the most out of your investment, it’s a good idea to plant them at a time of year when they will be most able to establish themselves well. Autumn is that time. The reason for this is that trees can take time to get their roots fully plugged into the soil once you have planted them. Planting now will afford them little time to develop an extensive enough root system to be capable of supporting the leafy crown through periods of stressful hot and dry weather during the summer. As a result, you may find that leaves become scorched and dry out in the sun, as the plant struggles to take up enough water to replace what is being lost through the canopy. A summer of this kind of stress can leave your tree in a rather sorry looking state, so it is far better to delay planting until we are once again approaching the cooler months of the year. In the meantime, you can visualise how your garden is going to look in the years to come, and enjoy perusing the great many perennials— which you still have time to plant, and which will provide supporting roles for your fabulous new trees.

A fine specimen indeed...

The trees that I have recommended below are mostly small to medium-sized trees, appropriate for smaller gardens, and varieties that most gardeners will have a hope of seeing grow to maturity without having to wait a lifetime or three. In most cases, you will have the option of single-stem or multi-stem specimens. The latter can be preferable in trees grown for the colour of their stems. Given the space, the designer in me would plant three of the same variety throughout a garden to bring unity to the design; however, the avid plant collector in me would most certainly select three different varieties, and would probably try to shoehorn in two more to boot. It’s a constant battle I have with myself. I will let you decide where exactly your own personal taste falls on this debate.

Cornus kousa ‘China Girl’

In early summer, every bough of this elegant Flowering Chinese Dogwood will be coated with large, star-like flowers, each comprised of four broad and pointed, creamy bracts, joined at their centre by a large green boss that appears to be studded with little pins. These will be followed by peculiar raspberry-like fruits in autumn, when the entire tree will turn a magnificent fiery red.

Cercidiphyllum japonicum

A tree that is perhaps better known by its common names, Candyfloss Tree or Katsura. This splendid species from Japan is celebrated for the delicious scent of slightly burnt caramel that its fresh green, heartshaped leaves emit during their annual procession through various shades of yellow, orange, purple and red before they fall in the autumn. Its heavenly perfume will fill your entire garden on a warm and still evening.

Cercis canadensis ‘Forest Pansy’

This variety of the North American Judas Tree is grown for its stunning Plum-coloured, heartshaped foliage. The leaves are preceded by showy clusters of magenta flowers that line each branch in mid-spring. Like the Cercidiphyllum, above, its season closes with a marvellous technicolour display.

Betula albosinensis ‘Fascination’

Despite its common name, Chinese White Birch, the peeling papery bark of this variety has a pretty salmon-pink hue. This contrasts beautifully with the chocolatey burgundy of the younger branches. Its dark green, diamond-shaped leaves will turn sunshine yellow in the autumn, before falling to carpet your garden with gold.