What Causes Hydrangeas To Become Blue?

The color of hydrangeas is directly controlled by the soil’s pH, making them desirable for lawn or garden gardens. One popular way to turn hydrangeas blue is by using aluminum sulfate, which lowers the soil’s pH level, making it more acidic. When the soil is acidic, the flowers bloom blue (rather than pink) when they are grown in acidic soil.

To turn a blue hydrangea pink or red, you need to reduce the acidic content in the soil by adding aluminum sulfate. To do this, mix ¼ cup of aluminum sulfate with compost and mix with vinegar or other natural remedies like coffee grounds, vinegar, or rusty nails.

Although vinegar may work to turn hydrangeas blue, it will take a long time for them to change color. To ensure your hydrangea stays really blue, add Vitax Hydrangea Colourant, a powder containing aluminium that can be mixed with compost. To encourage blue hydrangea flowers, grow the plant in soil with a pH of 5.2-5.5. If your soil is more alkaline, you can lower the pH by applying soil amendments like aluminum sulfate.

In summary, hydrangeas bloom blue when grown in acidic soil, and to turn them pink or red, you need to make the soil more acidic. Using aluminum sulfate is a proven method for changing flower color, and it is essential to use the right species for your garden.

What home remedy will turn my hydrangea blue?

Coffee grounds can be used to change the color of hydrangeas, but it’s best to use aluminum sulfate for a proven flower color change. Crushed eggshells may work, but they should be used with a proven method of raising the pH, like applying garden lime. Vinegar can be added to watering cans to change soil acidity and turn hydrangeas blue, but it’s not a long-term solution and can be harmful to local wildlife.

Does vinegar turn hydrangeas blue?

The addition of vinegar to the soil can result in the blue hydrangea’s foliage taking on a blue hue. However, this method is time-consuming and the effect is relatively short-lived. The practice of repelling beneficial insects and inviting destructive ones renders the method unreliable. The blue hydrangea is an ideal gift for occasions requiring an expression of regret or forgiveness. The flower symbolizes regret and remorse, making it an appropriate choice for such occasions.

What is the best fertilizer to turn hydrangeas blue?

Hydrangeas should be fertilized once in spring for blue cultivars of bigleaf and mountain hydrangea, using a low-phosphorous fertilizer like 12-4-8 to encourage blue flower production. For other types of hydrangeas, use a general-purpose fertilizer at recommended rates, incorporating dry fertilizer into the top 2-3″ of soil and watering thoroughly. Phosphorus in the soil can bind aluminum, making it difficult for the plant to access phosphorus.

How do I keep my hydrangea blue?

To maintain hydrangea’s blue color, add Vitax Hydrangea Colourant, an aluminium powder mixed with compost, or mix it into the soil surface each spring. White hydrangeas do not change color according to soil type but may blush pink in the sun. Regular watering is essential in pots and containers, and in dry spells in open ground. Add garden compost or farmyard manure when planting, and water thoroughly before and after planting. Hydrangeas hate dry conditions, so it’s crucial to maintain proper watering and feeding.

Will baking soda make hydrangeas blue?

Loamy soil has high soil buffering capacity, making it resistant to pH change. Baking soda, a small amount, doesn’t significantly impact the hydrangea’s color, as it leaves the pH unchanged. Adding more can damage roots and potentially kill the plant. For practical pH alterations, use soil amendments like sulfur to lower pH and lime to increase it, as these amendments have been proven to be effective.

Will aluminum foil turn hydrangeas blue?

The pH of the soil exerts a significant influence on the coloration of hydrangeas, particularly with regard to the quantity of aluminum that they absorb. The presence of aluminum in the soil is indicated by the blooming of pink flowers, while the absence of aluminum is indicated by the blooming of blue flowers. Modifying the pH can be an effective method for controlling the color.

Will lemon juice turn hydrangeas blue?

Gardeners can chemically manipulate hydrangea bloom colors using soil additives, which can result in different colors on the same bush if the roots sample soils of differing pH. Homemade recipes for changing hydrangea bloom colors include pouring vinegar or lemon juice on the soil, mulching the plant with coffee grounds, citrus fruit rinds, or pine tree needles, or burying rusty nails, old tin cans, or copper pennies next to the bush. However, the underlying chemical mechanism behind the color change is not soil acidity.

The color of hydrangea flowers depends on the availability of aluminum ions (Al 3+) within the soil. Aluminum ions are mobile in acidic soil due to the availability of other ions they can react with, which can be taken up into the hydrangea to the bloom. In neutral to basic soil, the ions combine with hydroxide ions to form immobile aluminum hydroxide, Al(OH) 3. To blue hydrangea blooms, both aluminum ions and acidic soil are needed.

The best soil additive for bluing is commercially available aluminum sulfate, Al 2 (SO 4 ) 3. To change blue-blooming hydrangea to red-blooming, adding lime results in basic soil and the desired color transition.