Boron Deficiency in Plum
Tip dieback and leaf fall, particularly on the upper branches, can be expected, but the main symptoms of boron deficiency will be formed on the fruit. Brown sunken areas appear in the flesh and sometimes gum pockets are also formed. Multiple branching is prominent at the tops of the trees. Flowering is seldom impaired by boron deficiency but as very many flowers fail to develop, there is usually a marked reduction in fruit set.