If the plants are thriving, there is no reason whatsoever, to use artificial fertilizers. Over-fertilization is harmful, because it causes excessive, exacerbated plant growth, which become less resistant to frost and disease and more vulnerable to pest attacks.
On the other hand, plants, which show symptoms of deficits, they absolutely need help. For example, Yellowing of the leaves and poor growth indicate a lack of enough nitrogen. Brown discoloration of the leaves and drying of the edges of the leaf blades are usually a sign of potassium deficiency, especially if it is accompanied by weaker flower development or worse fruiting. Yellowing of the leaves around the veins is a typical symptom of magnesium deficiency. Some plants have a particularly high demand for minerals. By deciding to enrich the soil with the right minerals, however, we should always use common sense and the results of plant observations. Fertilizers are best used in early spring, at the beginning of the growing season.
Let's remember, that diseased plants are usually unable to make proper use of the fertilizer. The weakened root system of such plants does not absorb the administered minerals, hence their excessive concentration in the soil, and this can harm plants even more. This situation is particularly dangerous for container crops.
The three main minerals, the so-called. makroelementy, to azot (N), Phosphor (P) and potassium (K). Generally speaking, nitrogen contributes to the growth of green mass, phosphorus on the root system, a potas na rozwój kwiatów i wytwarzanie owoców. These three macronutrients are always listed on the fertilizer packages in this order, along with information on the percentage share of each of them. Other important macronutrients are magnesium (Mg), calcium (That) and sulfur (S). Micronutrients also play an important role, such as iron (Fe), mangan (Mn), copper (With), zinc (Zn), bor (B) and molybdenum (Mo).
A wonderful treatment:
• A few years ago my Japanese cherry fell ill (Prunus serrulata). The leaves began to turn yellow and fall off. It might seem, that in late spring autumn has come to my garden. Fortunately, one dose of Epsom salt was enough – 200 g na 10 liters of water – for the tree to regain its healthy appearance. Cherry suffered from a lack of magnesium, whose shortages have been made up.