The soil is responsible for the color change
First of all, it is important to know that only the pink hydrangea species are able to change their color. The tint of the flowers is largely influenced by these points:
- pH of the substrate
- Aluminum content of the earth
- Initial color of the flowers
- Hardness of the irrigation water
also read
- Why does the hydrangea lose its color?
- Coloring hydrangea blue - how do you do it?
- The perfect location for the hydrangea in the garden
Achieve a color change to pink
For a blue hydrangea to have delicate pink flowers, the pH value must be shifted to the alkaline range. As a result, the plant also absorbs less aluminum and the flower color fades.
Lime the soil around the hydrangea several times a year until it levels off to a pH of around 6. Fertilize the hydrangea twice a year with a special hydrangea fertilizer to which iron is also added. This will prevent the plant from developing yellow leaves due to iron deficiency.
Sour makes you blue
The most sought-after flower color in hydrangeas is a beautiful blue or rich purple. So that the tint of the flowers turns blue, the pH value of the substrate must be in the acidic range. At the same time, there must be enough aluminum in the earth.
Acidification of the soil
Various means are suitable for this:
- organic material (compost, peat)
- Hydrangea or rhododendron soil
- matured crap
- Sulfur fertilization
- Pour regularly with vinegar water
Increase the aluminum content of the soil
If the substrate has a pH value of 5.2 to 5.5, you can apply hydrangea blue or aluminum sulfate. Check this value at regular intervals with test sticks that you can get from gardening shops. Hydrangea blue should always be used in the amount indicated on the packaging. If you prefer aluminum sulfate, you should dissolve two tablespoons of aluminum in five liters of water and water the plant with this mixture.
Tips & Tricks
Before treating with hydrangea blue or aluminum sulfate, it is necessary to water the hydrangea well. This is the only way for the plant to absorb the coloring agent well.
