Content
- Roses overfertilized? To avoid fertilizer damage
- Before fertilizing, the soil sample arrives
- How to recognize certain fertilizer damage
- Nitrogen surplus
- Phosphorus surplus
- Kalkchlorose
- Tips
Over-fertilization can express itself differently
Roses overfertilized? To avoid fertilizer damage
With optimal fertilization, roses develop substances that protect them from infestation with weak parasites. However, too rich or wrong fertilizers can cause an imbalance in the soil and promote a disease infestation.
Before fertilizing, the soil sample arrives
As various scientific studies have shown, many home gardens are over-supplied with nitrogen and phosphorus, but often lack potassium. Have a soil analysis done before planting, which of course makes sense even if your roses are often ailing. Many institutes offer special nutrient nutrient analyzes and can provide you with fertilizer suggestions that are specially tailored to your soil conditions. This allows you to compensate for both deficiencies and excess nutrients.
How to recognize certain fertilizer damage
Indications of certain disorders caused by over-fertilization can be easily recognized by the rose petals.
Nitrogen surplus
A lack of nitrogen is rare, but then shows by weak growth, small, yellowish-green leaves and little flowers. An excess of nitrogen in turn leads to soft shoots and leaves, which are increasingly attacked by aphids. Due to the nutrient surplus the rose shoots do not ripen, after all they are stimulated to continue growing, they can freeze and are also susceptible to mildew and the bark spot disease (also known as bark branding). You can counteract with a potassium fertilization, as this substance favors the maturity.
Phosphorus surplus
Also, a phosphorus deficiency occurs only very rarely. You can recognize him by the thick, blue-green leaves with the purple edges and undersides. On the other hand, phosphorus surplus, which in turn favors infestation with the blackspot, a harmful fungus, is much more common. Special funds available from specialist dealers can remedy this situation.
Kalkchlorose
One of the most common deficiency symptoms in roses, however, is chlorosis caused by an excess of lime. Too much lime content in the soil makes it difficult to pick up iron because it binds iron compounds in the soil. They recognize this nutrient surplus in the small, pale yellow leaves, where only the leaf veins remain green. Lime chloroses are particularly common on loamy, wet soils and as a result of the calcification of roses.
Tips
Roses should never be fertilized at planting, but only after successful growth. Otherwise, the roots can be severely damaged by the nutrient surplus. If you want to fertilize at the beginning, it is best to take horn shavings - they only become active when they decompose after a while. In general, organic or depot fertilizers for the supply of roses are better than artificial fertilizer.