Fertilizing plants at an inappropriate time can be counterproductive. Hydrangeas (Hydrangea) enter a growth phase in spring in which they benefit from additional nutrients.
Fertilization should not be carried out in autumn in order not to expose the young shoots to the risk of frost. Organic fertilizers such as rotted cow manure, cattle dung pellets or horn shavings are well suited for hydrangeas. The color of the flowers is also important: If you prefer a blue color with a predominantly pink-flowering farmer's hydranges, you must use alum or a special fertilizer.