It is important that potassium concentrations are in balance with other cations, particularly calcium, as preferential uptake of potassium over calcium will significantly increase the risk of rotten fruit and physiological disorders.
The most common diseases are rust, scab, different rots and fire blight. Attacks from a variety of insects and mites are frequent too. Good crop nutrition is essential to promote the health of apple plants and make them more resistant to pests.
It is important that potassium concentrations are in balance with other cations, particularly calcium, as preferential uptake of potassium over calcium will significantly increase the risk of rotten fruit and physiological disorders.
Storage rots including Gloeosporium rot and penicillium can be minimized by use of calcium. Repeated foliar applications are the most effective at alleviating this kind of damage.