Let there be LIGHT!

The clocks have gone forward, now give your plants the sunlight they crave by trimming back trees and shrubs, says Monty Don

As gardeners understand better than anyone, spring is not really about weather – goodness knows it can snow and hail and freeze and rain and blow all on the same day at this time of year – but about light. Sunlight is what we and our gardens crave more than anything else, even if it is filtered through cloud. The most exciting day of the year for me was last Sunday when the clocks moved forward to British Summer Time and we suddenly had that extra hour of light in the evening and the balance tipped so that now our days are longer than the nights, and are heading more and more in that direction daily.

But sometimes the lengthening days are just not enough and the gardener has to take matters into their own hands with what may seem like drastic action. This is exactly what I have been doing here in my Jewel Garden.

The Jewel Garden consists essentially of eight large beds right in the centre of the garden, planted entirely in rich jewel colours. For the past 20 or so years this has been a sundrenched spot and plants from all over the world have bathed luxuriously in its light, heat and rich, deep soil. But last year I noticed that far from being sun- drenched, it had in fact become remarkably shady. The explanation was unexpected but startlingly obvious: the trees that I’d planted 20 years ago had grown and were now blocking out the sun.

So in January we called in tree surgeons and cut down seven large trees on its fringes, which has let in light but not left an empty space – in fact, their absence is almost unnoticeable. And now, within the borders, I have cut back the huge purple hazels that were an important feature of the whole garden, removing the mature growth and just leaving a half dozen or so slender shoots to establish the new framework.

Although the individual hazels are much smaller than the trees we had removed, the impact is immediately startlingly dramatic – thanks to the large space where the hazels dominated – and hopefully over the coming few years light can once again pour unhindered onto the plants that need it.

But this is merely extreme pruning. And the fact that these were hazels ( Corylus maxima ‘Purpurea’) that I was cutting back means that they will regrow with increased vigour to whatever size I wish before being repruned, and this cycle can be repeated every five or ten years for centuries without any harm whatsoever coming to the plant at all.

Hazel is perfectly suited to this treatment but so too, in a garden context, are willow, dogwood and elder; and in woodlands, ash, oak, beech, lime, hornbeam and field maple. All these trees and shrubs can be regularly pruned back to a stump, flooding the area around them with light so the underplanting responds with a dramatic increase in flowering for a few years before the branches start to regrow and cast a shade that becomes increasingly heavy. The cycle of pruning can be as short as every other year in the case of dogwood or willow or as long as 30 years with oak. Just cut down to the lowest bud and the plant itself will not be harmed at all, with the existing root system able to focus its energies on renewing the top growth with increased vigour.

My purple hazel will be recycled down to the last catkin, making pea sticks, bean sticks, posts, kindling and eventually firewood. But the real harvest is light, light that will restore the vigour of plants that have evolved in South Africa, Central America and the Mediterranean but have, poor things, been starved of it, especially with our summers becoming so fickle and cloudy.

Now they can shine!

Monty with young hazels in his Jewel Garden