Foliar fertilization in fruit-growing
The foliar fertilization with micro-nutrients (e.g. manganese, iron, magnesium) is well established since many years.
Foliar fertilizers can be used preventive as integrated part of the fertilizer strategy or if it comes to an undersupply with nutrients and visible symptoms. The leaf analysis can help to analyze and recognize the availability for each element.
Many parameters in the soil can limit the availability of nutrients – high pH-values can block micro-nutrients, low pH-values can block macro-nutrients.
But also dry and cold weather conditions, soil texture and some nutrient antagonism (e.g. oversupply with potassium vs. magnesium and calcium) can lead to a deficiency of nutrients.
Apple trees are more sensitive to fertilization compared to pear trees. The nutrient nitrogen is necessary for high yield and potassium and phosphorus are stimulating the coloring and quality. But also a certain ratio between potassium and calcium is crucial for the fruit quality. An optimized nutrion with mangnesium and manganese will help to avoid leaf spots. Pear trees are more susceptable for iron chloroses.
Leaf spots and early leaf fall
Some varieties, especially Gold Delicious, Jonagold, Elstar, Gala and Cox are tending to nutrition based and physiological leaf necrosis and early leaf fall. This is caused by an undersupply and lack of manganese and magnesium. The combination of Lebosol®-Magnesium 400 SC with Lebosol®-Manganese 500 SC can optimize nutrition and reduce these effects.
Flowering, fruit setting and skin stability
Boron in combination with calcium (Lebosol®-Robustus SC), zinc (Lebosol®-Zinc 700 SC) and amino acids (Aminosol®) are crucial for the pollen tube growth, flowering and the fruit setting. The susceptibility to rust will be reduced. These products can be applied before flowering or after harvest. The application of Lebosol®-Robustus SC before flowering will enhance fruit coloration, the nutrients boron and zinc stimulating the calcium absorption, too.
Phosphorus and potassium are stimulating the coloration of the fruit. Lebosol®-PK-Max, containing both nutrients, can be applied from the beginning of fruit setting to stimulate the red coloring. The nutrient manganese is stimulating the green “background” color and can be applied with the product Lebosol®-Mangan GOLD SC especially in two-color varieties.
As mentioned above, pear trees are sensitive to iron deficiency. Symptoms are iron chloroses and will be visible by a yellowness of the youngest leaves with dark veins. Different paramters, e.g. soil structure, moisture and pH value will influence the iron availability. The foliar fertilizer Lebosol®-Eisen-Citrat GOLD – containing iron and manganese - will enhance the iron and manganese supply and availability. For better spreading and uptake, the product is formulated with amino acids as well.