Pruning Trees and Shrubs After a Harsh Winter

Snow is magical but the inevitable makes our gardens look pretty tawdry, uncovering so much damage. But things may not be as bleak as they look.

Prune trees

When we have lots of snow, branches either break off or are flattened, possibly damaging surrounding plants and the temptation is to cut out the damage. Branches that have fallen on a path or are throttling a neighbour clearly must go: cracked or split ones will almost certainly have to be removed, even if, like a plum tree, they shouldn’t be pruned just now. Some stems may also need to be cut down to the ground or, if part of it is undamaged, just prune back to a join. But leave any major pruning for a milder, frost-free, spell of weather to avoid any needless die-back.

Prune roses

Heavy snow takes no prisoners: a rusty or frail rose arch is doomed. Lash up a temporary repair, loosely attach the rose or honeysuckle, and install a new frame later when the shrub is pliable. You can then safely detach and bundle it to one side during the reconstruction. In my own garden, one of my ramblers, Paul’s Himalayan Musk was partly dislodged from its tree by snow, so clearly had to be reinstated as soon as the stems stopped being frozen. My small Syringa meyerii ‘Palibin’ also lost a branch, but it suffered more damage from nibbling voles, safely hidden beneath their white blanket.

After these emergency repairs, I would recommend leaving a major overhaul till after the worst of the cold weather. If the winter isn’t over, wait till the final picture emerges. Not only that, but before then, you can’t be sure how well, if at all, a shrub will recover. The rose hedge round my kitchen garden certainly took a pasting last year. Most of this wide hedge was flattened and spread out to three times its original width. Of course, a lot of it recovered, but how much and how severely I pruned depended on what it was like at the end of the winter.

Be patient

Not only that, but by leaving a plant alone, with its stems intact, you’ll protect the crown and give it a better chance of recovering. Some herbaceous perennials may well be slower than usual to burst into life; it is surprising how much longer this can take. Naturally, it could be well and truly dead, and after a harsh winter, the border may have some corpses, but be patient!

Plants protect themselves

As we’d expect, plants have had to develop many defense mechanisms against the cold. In sub-zero temperatures, ice crystals form between the cells in a plant, as the liquid is drawn from the cells. This frozen water is useless to a leaf or stem, and the dried out cells will collapse as the ice crystals expand. Many woody shrubs and trees protect themselves by withdrawing water that could freeze, while other plants, like daffodils, produce the equivalent to anti-freeze. What we call ‘hardy’ plants have found a way to cope, tender ones will frizzle and die, while our ‘semi-hardy specimens need all the help that even snow can provide. A snowy winter is the acid test for the plants in our gardens!