Winter pruning of limes, hazels & dogwoods

Hard pruning takes courage and gardeners are often reluctant to carry it out for fear of harming or, even worse, killing the plant. Once it is understood that more trees and shrubs are lost through neglect than by pruning the task becomes somewhat easier. In far too many gardens woody plants are grubbed out because they have outgrown their allotted space when judicious pruning at an earlier stage of their life would have allowed them to thrive and give pleasure for many more years.

Outgrown its space? Don’t remove it, prune it!

January and February are the perfect months for carrying out coppicing and pollarding and some shrubs like willow and dogwoods, grown for the winter colour of their bark, are actually improved by the process. Coppicing and pollarding are traditional techniques that have been carried out for centuries in woods and forests to provide a plentiful supply of fuel and fencing materials. As with all procedures, jargon evolves and coppicing and pollarding are just words that describe the removal of branches back to the tree trunk (coppicing) or, in the case of pollarding, the removal of stems to ground level. Somehow, if you just say to yourself, “cut off every branch” the mystery of the process disappears and becomes less intimidating.

Willows – some newly pollarded line a riverbank

Limes (Tilia) are very beautiful when grown as full-sized trees but become far too large for most gardens. They are better planted as parkland trees in a field, if you are lucky enough to own one, where there stature and grace can be appreciated from a distance. Too often they are grown where their branches overhang driveways where they drop their sticky honeydew over vehicles and become a nuisance. Most limes are host to tens of thousands of aphids (greenfly) which feed on its sap and then secrete the unwanted waste. Somehow, the gardener’s jargon word ‘honeydew’ sounds so much nicer than ‘greenfly crap!’ If you are determined to plant a lime tree in a confined space the Caucasian Lime, Tilia x euchlora which doesn’t have this problem is the one to go for. Remember that any tree in a confined space will need its size controlled so read on to find out how to pollard it.

Limes, when mature, are beautiful but very large trees

The time to pollard a tree is winter and January, when there isn’t too much to do gardening-wise, is the perfect month. I always aim to complete by the 31st which allows time to continue into February, if need be. By the middle of that month the sap will be starting to rise within the tree so it is sensible to complete the task by then. It is very straightforward to remove the branches for which you will need secateurs for smaller twigs, loppers for larger ones and a sharp pruning saw for anything bigger still. Which tool to use when? That too is easy to know. Secateurs and loppers should cut through the stems easily – if you need to twist the tool or the stem, you should be using the saw.

By midsummer there is plenty of new growth on this old willow pollard

Common sense will tell you that if you remove all branches from a tree there will be nothing left to offer any screening. This isn’t always important and coppiced trees send out new growth very rapidly as the weather warms up. However, for privacy or a different ornamental effect more careful pruning is required. All that needs to be done is to cut back any branch or twig that has grown beyond the space you have allocated for it.

A pollarded lime allee provides drama and a focal point

This lime allee has had its side branches retained to give denser summer screening

Limes are not often grown for the colour of their winter twigs probably as they are up rather high and so less noticeable. Willows (Salix) (when coppiced, for they can also be pollarded) and dogwoods (Cornus) are very different for their bright yellow, orange or scarlet stems are very visible and a mainstay for any winter garden. They are also quite simple to prune as it is all carried out at ground level. When the plants are mature, I prefer to cut them over a three year period as this retains their overall height. Quite simply, it means that only a third of the stems are removed or, if you have plenty of shrubs, completely prune one in every three to their base. The purpose behind this pruning is not so much to control their size but to maintain the strength of colour which is at its best on younger shoots. If left, they gradually become quite dull.

The coloured stems of dogwoods

Hazels are treated very much like willows and dogwoods, although the usual purpose is purely to maintain a convenient size or to provide ‘pea sticks’ to be used for supporting summer plants as well as peas and beans. For guidance take a look at my earlier post from 2021 which can be read by clicking on the link here.

A hazel tunnel is created by partial coppicing to reduce the number of tall stems