As you know, hydrangea feels really good only on acidic soils, which directly affects the quality of its flowering.
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If only a bunch of bushes grew on your plot, then you need to acidify the soil.
However, this is not enough. It is necessary to constantly maintain the necessary level of acidity for hydrangea.
Those who are faced with such a problem should seriously think about mulching. Sawdust or coniferous needles can be used as a covering material.
In addition, do not forget to apply garden sulfur - up to 10 g of the substance is needed for each "square".
If you plan to feed hydrangeas, give preference to such fertilizers as amphos, urea, ammonium sulfate, superphosphate.
It is most effective for this purpose to use irrigation with acidified water, which can be prepared by adding a tablespoon of 9% vinegar to a bucket of water.
As an alternative - citric acid. In this case, you will need 5 g per 3 liters of water. You can use such solutions once a month.