Our gardening expert reminisces about the days spent learning the names of some of the most obscure plants in Britain, and how it has enriched his life since then.

On winning the Nobel Prize for Literature in 1995, Seamus Heaney explained that he would spend some of his prize money on an educational course that would enable him, on walking through woodland, to identify the trees and the plants around him – something he had yearned to do all his life.

I have never forgotten the moment when he confessed this, as it gave me a certain amount of pride in my own ability. (It was tempered by the fact that the literary merit of my poetry fails by a significant margin to equal that of Mr Heaney, but that’s not the point.)

When I was a student at Kew Gardens between 1969 and 1972, the weekly plant identification test was the bane of our lives. Twenty plant specimens, gathered from the gardens’ vast and unparalleled collection – under glass and in the open – would be displayed in tall glass jars on the laboratory benches. In silence I would, along with the other students in my year, pass from one to another writing down against the corresponding numbers on a sheet of paper my best guess as to the family, genus species and variety of each plant. A score of 20 out of 20 was a cause for celebration at the end of the week in the Coach and Horses.

Kew Gardens

Kew Gardens

Some of the plants I learned I’ve never set eyes on since, but I bless those days – and the daily proximity to the finest plant collection in the world – for acquainting me with the wonders and variety of the Plant Kingdom at every time of year. There were certain horrors, of course, such as a week in which every specimen was a species of pine. Pines do vary in their appearance when examined at close quarters – their needles may be long or short and clustered in twos, threes or fives – but they send the mind reeling when it comes to remembering which is which.

In winter, the puzzle was further compounded by a total lack of foliage on deciduous trees, but learning to differentiate between oak and ash, beech and birch has stood me in good stead over the years. There is a degree of personal satisfaction in being able to tell t’other from which.

Some people give trees not a backward glance when they’re naked of leaves. They tower over us, naked and threatening, swaying in strong winds, bleak of countenance and seemingly devoid of life, but observing them in this state at close quarters is not without its pleasures, from the slender quill-like buds of beech to the tightly packed and folded nubs of the oak, encased in a plenitude of rufous scales.

Ash are easy to spot, their bullet-hard shoot tips being blackened as if by fire, and, with a bit of practice, you can learn to tell hornbeam a mile off by the wonderfully statuesque wide-open flame shape of its branch framework.

An avenue of beech trees in winter

Most of my generation learned to identify horse-chestnut twigs at junior school. ‘Sticky-buds’ we used to call them and we cut 3ft lengths and put them in jars on the high windowsill of our Victorian-built classroom to watch the toffee-coated leaf scales burst open to reveal the squashed and hairy umbrellas of leaf as they expanded almost before our eyes.

They and the germinating broad bean seeds, sandwiched between the sides of another glass jar and a cylinder of pink blotting paper, were our first introductions to the magic of plant growth.

I try still to expand my plant vocabulary, especially in winter, when there seems to be little in the way of botanical activity, but this is the time of year when trees in particular reveal their secret sides – the Jekyll or the Hyde of their character, depending on which way you look at it. There’s a particular kind of pleasure in identifying them in their dormant state – it’s the difference between doing the quick crossword and tackling the cryptic one.

There are some, of course, that surprise by the brilliance of their bark at this time of year: the paperbark maple, Acer griseum, with its peeling wafers of mahogany; the Tibetan cherry, Prunus serrula, as shiny as any sideboard regularly treated with Antiquax; and the birches, from ice-white Betula utilis var. jacquemontii through creamy Betula ermanii to the pinkish-orange tones of Betula albosinensis septentrionalis Kansu.

Dormant they may be, but there is still fun to be had from trees in winter – not least, remembering how to spell their Latin names.

Alan Titchmarch

– – –

My Secret Garden by Alan Titchmarsh is published by BBC Books