Foliar Application of Some Macronutrients and Micronutrients Improves Yield and Fruit Quality of Highbush Blueberry (Vaccinium corymbosum L.)

Foliar fertilization makes it possible to quickly provide plants with essential nutrients, mainly micronutrients, which can significantly improve the quality of yields. The aim of this study was to evaluate the effect of foliar fertilization with fertilizers containing calcium and microelements on yielding and fruit quality of highbush blueberry (Vaccinium corymbosum L.). A two-year study was carried out in western Poland in an experimental highbush blueberry production plantation. During the growing season the bushes were treated several times with the following foliar fertilizers: Armurox, BioCal, and Stymjod. The experiment assessed bush growth vigor, yield, fruit quality characteristics, sugar, organic acid, and health-promoting substance content. It was found that as a result of fertilizing highbush blueberry bushes with foliar fertilizers, the leaf blade area and plant yield increased significantly. The fruits collected from those bushes were characterized by a higher mass, firmness, and TSS content. This also applies to blueberry fruit after storage. Foliar fertilization had no significant effect on the content of chlorophyll a and b in the leaves of northern highbush blueberry, on fruit coloration, the content of sugars, ascorbic and citric acids, and the phenolic compounds in them.