Snow, Frost and Trees

As we are having a second year of very snowy and frosty weather I thought I would offer a little advice and information on how trees cope with this weather and anything we can do to help.

Deciduous trees.

Deciduous trees that are hardy to Britain will be fine in this weather, part of the reason they drop their leaves is to cope with sub zero temperatures.  This being said some flowering trees that have had buds on them through the winter such as magnolias may well not flower this year as the buds have been frozen.  If you have a newly planted tree, once the snow/frost has melted it is worth checking it is still firm in the ground.  Due to a process called frost heave,  the soil expands when it freezes then contracts again during the thawing process and can cause the roots to move in the ground.

Evergreen Trees.
Evergreen trees have a harder time in frozen weather, the rather obvious reason for this is that they still have leaves on. This causes two main problems the first is what is  a physiological watering disorder due to the fact that they are still growing. Evergreen trees never stop growing they just slow down significantly throughout the winter.  This results in them still needing water and when the ground freezes they can’t get it, much like a drought in the summer.  The second problem is that the water in the cells of evergreen plants freezes causing some damage to the cell walls. Evergreen trees and plants that are hardy to the UK have a number of mechanisms to cope with these problems and while they may look a little sad they should pick up well once the spring is upon us and they start to grow at a good rate again.

As always comments and questions are welcome.

Simon