Hi Jonathan, I am from Switzerland and work with Phytosolution products in Germany, they chelate micronutrients with “carbonic acid” (probably citric acid). I have had good experiences with Carbo Eco Mn as a foilar. Since your soil already has high Ca levels, I would recommend adding only elemental sulphur to the soil instead of gypsum. Use finely ground calcium with a fulvic acid or the Carbo Eco Ca from Phytosolution as a fertilizer. When the sugar level rises, the plants have more energy to absorb the calcium from the soil. Continue to add 1 kg of boron per year and of course biology with compost, extracts or teas.