Простой и двойной Суперфосфат, а также Аммофос для винограда

I intentionally did not include a detailed description of the effect of phosphorus on grape leaves, since, unlike nitrogen or potassium, the effect of phosphorus application is not visually noticeable and does not manifest itself in either the leaves or the growth of the grapes. Scientists are still debating the effectiveness of foliar phosphorus fertilizers. Personally, I find them beneficial on carbonate and sandy loam soils. Israeli winegrowers successfully use foliar feeding on grapes, including phosphorus. Reasons for poor foliar phosphorus uptake. Phosphorus in plants is almost never recycled through the leaf apoplast. Due to electrostatic repulsion, phosphate ions poorly penetrate the cuticle and cell walls. Unlike potassium or urea, phosphates do not pass through stomata or cuticle. Here are some examples of comparisons with magnesium. Magnesium (Mg²⁺) Size: Small (~72 pm ionic radius), positive charge Phosphorus Large (~240–300 pm equivalent radius), negative charge The smaller the ionic radius and the lower the charge, the better the penetration. But charge is more important than size: anions (negative ones) are less permeable due to repulsion from the negatively charged cuticle. Grapes have a very developed waxy coating on their leaves and even more so on their berries. The cuticle is thicker than that of many vegetable crops → even worse penetration.