Modern horticulture in Ukraine, at least its commercial segment, has almost fully switched to modern crop care technologies throughout the whole growing season, so the foliar feeding system is used quite widely and a large number of special fertilizers of foreign and domestic production are used for it. Foliar feedings of fruit crops are carried out in the most critical periods of their growth and development.
For bearing orchards and berry plantations the spring period is critical, both for plants' biological needs for nutrients and for weather conditions, especially temperature cataclysms during and right after flowering. In spring 2017 late frosts caused noticeable losses to growers in all regions. Unfortunately it cannot be certain that such a situation will not repeat this year, so it is better to prepare for it in advance. European experience in such cases provides for foliar feeding with potassium.
Potassium promotes the growth of xylem vascular bundles, thus improving the ability to transport and accumulate carbohydrates, and raises plant resistance to stress under drought, high and low temperatures. It is absorbed quickly by plants, about 70% of the applied amount in three hours. In addition, potassium strengthens calcium uptake from the soil, which ensures recovery of vascular bundles in the fruit stalk damaged by low temperatures and thus preserves the future yield.
On this basis, and taking into account positive experience of use, for foliar feeding in orchards after flowering we recommend the tank mix Ecoline Phosphite (K) 1.5–2.0 l/ha + Gros Health 1.0–1.5 l/ha.
The combination of potassium and phosphorus in the form of phosphite, readily available to plants, which raise plant immunity and move quickly through vascular bundles, with an anti-stress agent containing L-α amino acids and phytohormones from the three main agronomically valuable groups, auxins, gibberellins and cytokinins, promotes quick recovery of growth processes, thereby minimizing possible yield losses.