Cracks in the bark of apple trees

Garden Experts
Dear Mr Kötter, today my neighbour opposite showed me cracks in the bark of his apple trees. I told him I had experienced this where I lived before, and that it was due to the contrast between frosty nights and warm daytime sunshine. I advised him to paint a thick whitewash on the trunks and to lean planks against the trunks on sunny days. Did I give him good advice? Maybe you could write a couple of lines about this so I can pass the information on to my neighbour. As a professional, I imagine that you probably, or rather, certainly, have some extra advice to give me. I look forward to hearing from you.

The GARDENA gardening expert

The explanation you gave your neighbour and the preventive action you suggested were indeed well founded. However, I fear the advice on prevention has come too late. The best thing for him to do now, since his apple trees already have frost cracks, is to treat these wounds by cutting cleanly around the frayed edges of the cracks with a sharp pruning knife to remove the dead bark. This makes it easier for the inner layer, under the outer bark, to heal the wound through the coming year.

To prepare for the following winter, the clean wound can then be painted over with whitewash again. And bear in mind that the whitewash can also be applied to the base of the branches as frost cracks can appear here too. You will find a suitable whitewash product here: