Boron Deficiency in Raspberry
Failure of the fruiting canes to develop normally in the spring is one of the first signs of boron deficiency. Death of buds on the canes and failure to produce normal laterals give the bush the appearance of suffering from a “dieback." Berry production in such plants is likely to be considerably reduced.
Buds that develop are likely to show distorted leaves with some edge necrosis and unusually large petioles. Pith necrosis occurs. In less severely affected buds, leaves are small, thin, and deeply indented, giving a “feathery” appearance. Leaf crinkling also occurs. The lack of development of the old canes often results in a profusion of new canes from the base of the plants which will usually carry fairly normal leaves.