How to dye garden hydrangeas blue?

More than once you have probably wondered how it is that a neighbor has beautiful blue or even purple hydrangeas, and yours have such a common, pink color. Or maybe you bought a beautiful blue baby, and a large pink bush grew up? And how is it that it changed color?

There's nothing to worry about. It's not the fault of poor care. One of the factors responsible for the color of hydrangeas are compounds contained in flower petals, "chameleons" that change color depending on the pH of the surrounding environment. These are anthocyanins. It may sound scary, but it is a harmless and naturally occurring compound in plants, mainly in their fruits and flowers. It is also used as a food coloring.

Why is my hydrangea pink?

While pink hydrangea is often found in gardens, blue is less common. The reason is that she needs a little help to achieve this color and this help should be regular. To obtain a pink or red color, it is enough to plant the hydrangea in a place where the soil is alkaline. With regular watering and fertilization, it will repay you with its beauty.

How to get a blue color of hydrangeas?

Obtaining a blue color is associated with acidification of the soil on which our hydrangea is to grow. There are several ways to obtain an acid reaction. You can, for example, mix the soil with acidic peat in the place where you want to plant a shrub or water the soil with special acidifying fertilizers. At pH 5.5, the effects of our work can already be seen. The lower the pH, the more intense the color. However, you must remember not to overdo it and not to exceed the pH of 4.5. As for the soil, it is also important that it is humus, permeable and fertile.

Aluminum sulfate when pH is not enough.

However, even if we managed to obtain a soil with a pH appropriate for blue, the hydrangea will not discolor if there is a lack of one very important ingredient in this process, aluminum. Anthocyanins contained in flowers take on a blue color in an acidic environment, provided that they have access to aluminum. The anthocyanins bind to the aluminum and the resulting compound is light blue to purple in color. Aluminum is best introduced to the soil in the form of sulphate in the autumn, from 15 to 50 g per plant, depending on its size. Then, from spring, regular watering with aluminum sulphate solution begins, approximately once every 1-2 weeks, at a dose of approx. 10 g per 2 l of soft water per one lush plant. The treatment is carried out in addition to regular watering. Hydrangea is a flower that needs a lot of water to bloom beautifully, this need should not be neglected.

Water is not equal to water. So, how to water hydrangeas?

If we want to keep the blue color, we also need to pay attention to the water we water the flowers with. Water rich in calcium will, in a way, wash the color from the petals, because instead of binding to anthocyanins and giving a blue tint, aluminum will bind to calcium in the soil and will not even reach the petals. This will also deacidify the soil. Therefore, rainwater that does not contain calcium is the best.

Will my hydrangea definitely turn blue?

The most popular variety of garden hydrangea is Hydrangea Macrophylla and it is this variety that is the easiest to discolor. Others, maybe a bit less popular, but also dyeing blue are: Bodensee, Enziandom, Nikko Blue, Otaksa, Queen Elizabeth. There are species that, despite our efforts, will never get the color of the sky. The same applies to the white hydrangea, whose petals are devoid of anthocyanins responsible for the blue color.

Aluminum sulfate available at distripark.com .

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*This article is for informational purposes only. The presented description, in particular the use of the products, is exemplary and constitutes non-binding information about the characteristics and possibilities of their use/application. In any case, before using the product, consult a specialist whether the specific use is safe and justified. We do not bear any responsibility for the use of the proposed solutions, even in very similar situations.