Care tips - and all about blue hydrangeas

Here we give you simple care tips and reveal which hydrangeas turn blue and for what reason.

Abracadabra - hydrangeas that turn blue

Blue hydrangea does not exist by nature. Only the composition of the soil causes flowers to turn blue.

But this is the case only with (most) pink Hydrangea macrophylla and Hydrangea paniculata. Pure white or red flowers cannot be changed. In addition, the color change takes some time and is usually not complete until the second year.

Acidic soil and alum are prerequisites

For blue flowers, an acidic soil (pH value of between 4 and 4.5) is important, as is the case with rhododendrons, for example. Therefore, it is best to take special soil for rhododendrons or water with «Hortensienblau», which makes the soil acidic.

For the blue color you also need alum (aluminum salt), which is available in garden stores. To maintain the acidic soil (especially when planted in containers), you should use very soft water (e.g. rainwater) for watering.

Hydrangeas? They need a lot of water ...

Actually, almost any location is right for a hydrangea. However, since it needs a lot of water, a wind-protected spot in partial shade is best. Also ideal is a fresh, well-drained and nutritious soil that is slightly acidic to neutral.

Speaking of water, provide sufficient moisture, especially in dry and warm weather, but at the same time make sure that there is no waterlogging. If the heat is persistent, hydrangeas should be watered in the morning and evening, because they evaporate a lot of water through their many large leaves.

Hydrangeas are not always hardy

In principle, hydrangeas are hardy. But to be on the safe side, you can protect them from frost with some brushwood.

For potted plants, the container should have a diameter of at least 30-40 cm. Smaller containers should be wintered in a frost-free, but cold place at about 3-5 degrees C.