For those of us who garden, it’s hard not to see the countless parallels between the arc of a human life and that of a tree, right from infancy to old age.
Both are hard-wired to seek out shelter, nourishment, and a suitable spot to put down deep roots, as well as with a desire for community. Each is shaped in a myriad of ways by their environment, as well as vulnerable to the challenges of sickness and old age. Both are also part of a complex ecosystem upon which they depend on for their wellbeing, learning to share precious resources as a way of greatly upping the chances of survival.
In the case of trees, they do this by means of vast underground fungal networks made up of microscopic mycorrhizae- the “woodwide web”- through which they can share water, carbon, nitrogen and other important nutrients. Known as “mother trees”, the largest, oldest trees in a woodland typically have the most extensive fungal network, through which they help support younger, more vulnerable trees in need of assistance. In this way a woodland is remarkably similar to human society at its best, a model of peaceful co-operation.
Even the biochemical processes that humans and trees rely on for their existence are deeply intertwined. Ours rests on our ability to breathe in oxygen and then exhale carbon dioxide. That process of respiration is the perfect mirror image of photosynthesis, where trees take carbon dioxide and convert it into energy, a vital byproduct of which is oxygen.
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On a philosophical level, trees have long served as a powerful metaphor for the passage of time as well as the qualities needed to lead a long, healthy and fulfilling life; fortitude, resilience, a generous dollop of good luck, strong genes and adaptability.
They’re also inspiring. For anyone contemplating useful ways in which to move forward with their life or to institute changes for the better, just take a look at a mature beech tree and contemplate the fact that it started life as a beech nut, no bigger than a two-cent coin. Likewise, when the American writer Ralph Waldo Emerson wrote that the creation of a thousand forests is in one acorn, he meant it metaphorically and literally.
Plant just one tree in your garden and it’s the beginning of something potentially far greater than you could envisage. A rich habitat for wildlife. A metronome of seasonal change and the natural cycle of life, death, decay and rebirth. A source of shelter. A beacon of beauty not just for its owner but for all who see it, as well as a companion for life.
I say all the above at the risk of repeating myself from previous columns because we need more garden trees. Because I see so many young gardens whose owners are so caught up in the busy hustle of modern life that they’ve yet to plant a single tree, or to realise that, unlike ephemeral summer bedding that dies with the first harsh frost, trees are the gifts that keep on giving
Mid to late autumn is the perfect time to get them in the ground, while soils are still warm from summer’s heat but replenished by recent rainfall. If you’ve no clue as to what type of tree you’d like to plant, then there are some basic ground rules to bear in mind.
First and foremost, try to choose one that suits the size of your garden as well as its growing conditions in terms of light, soil type and shelter. For example, if yours is a cold, damp, exposed garden prone to winter waterlogging and vulnerable to blustery gales, there’s no point in choosing something like a Japanese acer which requires shelter – ideally in dappled shade – and a moist but well-drained soil to flourish.
Instead consider ultra-tough, hardy species such as birch (Betula), hornbeam (Carpinus), mountain ash (Sorbus), paperback maple (Acer griseum) or hawthorn (Crataegus). If it’s a large garden, you could also consider tupelo (Nyssa sylvatic), sweet gum (Liquidambar), alder (alnus), poplar (Populus) and swamp cypress (Taxodium).
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Alternatively, if yours is a small, sheltered town garden then there may be scope to grow more compact, shelter-loving kinds such as the star magnolia and the fairy magnolia (Magnolia), dogwood (Cornus kousa), snowy Mespilus (Amelanchier), Japanese acer (Acer palmatum), ornamental crab apple (Malus) and flowering cherry (Prunus).
Whatever you choose, consider its position in terms of any eventual shade it might cast as well as its probing root system when mature. Few things are sadder than having to either remove or drastically reduce the canopy of a much-loved tree that’s either outgrown its site or whose root system poses a threat to the foundations of buildings, septic tanks or other underground structures such as drains.
That said, it’s important to note that the great majority of trees, even those planted close to buildings, typically don’t cause this kind of damage, as well as to bear in mind that any potential for damage greatly depends upon the soil type as well as the species of tree. Heavy clay soils, for example, are more vulnerable to shrinking in summer droughts, while thirsty species such as poplar, oak, willow and eucalyptus pose much more of a threat than less thirsty species such as magnolia, pine, liriodendron and catalpa in terms of possible subsidence.
While pointing out that there is an overly cautious attitude by insurance companies and local authorities to planting larger trees in built-up areas – an approach with significant health and environmental consequences for us all – the UK’s RHS (Royal Horticultural Society) suggests using the eventual height of the tree as a rough guideline. In damp, heavy clay soil as described above, this means keeping trees at a distance from buildings that’s equivalent to the estimated height of the particular species/variety when mature. In other soils, half this.
Plant into well-prepared soil, making a wide, roughly square-shaped hole and pre-soaking the rootball before placing it to the correct depth, so that the point where the tree’s roots meet its trunk is at or just above ground level.
Refill the hole, gently firm the ground with your feet, give it a generous watering and then mulch around the base with an organic mulch to a depth of 5cm, taking care to keep it out of direct contact with the trunk. It’s a process that takes all of an hour from start to finish but will result in a lifetime of joy.
This week in the garden
Clear faded plants from glasshouses and polytunnels, finishing off with a protective soil mulch to suppress weed growth. To keep any overwintering crops healthy, continue to ventilate these covered growing spaces well during the day before closing them up at night. Watering should be carried out in the morning to reduce the risk of disease.
As temperatures fall and night frosts become likely, compost heaps will really benefit from a waterproof cover as well as some extra insulation (examples include straw, woodchip, cardboard, fallen leaves) to keep out excess winter rainfall, lock in heat and help the process of aerobic decomposition to keep humming along.
Dates for your diary
Altamont Plants, Walled Garden Altamont, Kilbride, Tullow, Co Carlow; today (Saturday, October 13th) and tomorrow (Sunday, October 13th). Series of practical talks by expert gardeners including Mary Keenan of Gash Gardens, Hester Forde of Coosheen Garden, and Dave Hardy of Esker Farm Daffodills, pre-booking essential, see altamontplants.com.
