The low autumn temperatures and excess humidity are calling for action in terms of P-supply.
The symptoms appear first on the leaves, especially after a prolonged period of low temperatures and on soils with excess moisture and low permeability.
The growth of plants is reduced and the coloration of the leaves is characterized by shades of reddish-purple. The more intense the discoloration, the greater the phosphorus deficiency. The growth of roots and the development of the radicular system is poor.