How to Change the Colour of Hydrangeas Using Simple Trick

Hydrangeas are known to change their colour depending on the soil conditions. By soil conditions, it means that the colour of hydrangeas depends on the soil’s pH level. A lower pH level determines the blue color of the flower. That said, there are simple ways to change the color of hydrangeas, and we will discuss them in this article. 

The color-changing phenomena in hydrangea were noticed by people as early as the 18th century. It is simply magical to see how these flowers can change their hue over time and transform into a completely different shade. But as much as it may look like a miracle, it is purely based on scientific reasons. 

What Makes Hydrangea Change Their Colour? 

The amount of acid present in the soil decides the colour of the hydrangea. The amount of acid in the soil can be identified by testing its pH level. On the pH scale, seven is considered alkaline, and any value lower than seven indicates acidity. 

So, if the soil’s pH level is anywhere between 6 to 7, the hydrangeas will be purple or bluish pink. And if the pH level is below 6, the hydrangeas will turn blue. 

Another factor that changes the colour of hydrangeas is the presence of aluminium in the soil. You must have noticed that pink hydrangeas look much prettier than blue ones. That pretty shade of pink exists in hydrangeas due to the presence of aluminium in the soil. Higher pH levels in the soil lock the aluminium in the soil and the flowers turn pink. Well, it may seem a bit confusing now, but don’t worry, it is soon going to get more clear!

How Does Different pH levels Change the Colour? 

If you think the variance in the pH levels is the sole reason for changing the colours in hydrangea, then no, it is not the only reason. However, pH level does control the absorption of aluminium in the plants that decides the colour. 

Aluminium is the most important factor in determining the colour of the flower. It is easily available in the soil. When the soil’s pH level is low, it increases the absorbency rate of aluminium, therefore changing the colour of hydrangea to blue. And when the soil contains higher pH levels, it reduces the absorbency of aluminium. Therefore the flowers turn pink. 

Here is how different pH levels lead to different colours in the flowers:- 

1. pH 5.0 to 5.5 – blue colour
2. pH 6.0 to 6.5 – pink or purple colour
3. pH 5.5 to 6.5 – purple, blue, and pink colour 
4. pH above 7 – red and pink colour 

This Is What You Can Do To Change The Colour of Hydrangeas

You may have purchased a certain colour of hydrangeas from the nursery, but their colour may change due to the type and quality of the soil in your garden. If you want to adjust the colour of the hydrangeas to your favourite colour palette, here’s what you can do:- 

To Turn Your Hydrangeas Blue 

You can increase the acidity of your soil by mixing any of the following things:- 

• A mulch of pine needles
• Compost
• Coffee grounds
• Vinegar mixed with water
• Leaf mould
• Organic liquid feed

Fruit peels, peat moss, and lawn clippings can also do the trick. You can also add aluminium sulphate to maintain the amount of aluminium in the soil, which is the main ingredient in changing the colour of hydrangeas. 

To Turn Your Hydrangeas Pink 

If your soil is already acidic and turning your beautiful pink blossoms into blue, don’t worry. You can easily transform their colour into a beautiful shade of pink. When the soil is more alkaline, it locks aluminium, making it difficult for the plants to absorb it. So, to make your soil alkaline, you can add any of the following things to your garden soil:-

• Powdered garden lime
• Crushed eggshells
• Baking soda
• Wood ash 
• Dolomite lime 
• Cement kiln dust 

But before you begin experimenting with your garden soil, you need to take care of the following things:- 

Don’t Plant Vegetable Gardens Next To Hydrangeas 

Not all plants can endure changes in the pH of the soil. Some plants thrive on acidic soil, whereas some grow best in a neutral pH. Vegetable plants are one such example. So, if you want to carry out this experiment, try not to disturb the soil of other plants unless they can grow in highly acidic or alkaline soil conditions. 

Give Newly Planted Hydrangeas Some Time to Adapt 

Newly planted flowers need some time to adapt to their surrounding environment. You don’t want your lovely blooms to get a plant shock – yes, it happens! Plants also get shocked due to sudden and abrupt environmental changes, such as changes in light conditions, temperature, and even over-fertilising can damage the newly transplanted flowers. So, extreme changes in the soil condition of a newly planted hydrangea can also be harmful to its growth. 

Spring or Fall is the Best Season For Bringing Changes in the Soil 

Plants get the most time to absorb aluminium during the spring or fall season. So, you should probably wait till the best season to experiment with your soil to see the most exciting results. And it is essential to remember that these changes can take a few days or weeks to show up. So, don’t get disheartened. Wait patiently while your pretty flowers change their colour.   

Treat Your Soil Regularly 

Altering the pH levels of the soil once or twice is not enough. To see better and long-lasting changes, you must regularly treat your soil with pH-changing products. When you add any such product to your garden soil, the pH levels change, but the soil returns to its original pH level over time. So, it becomes necessary to treat the soil regularly. 

Conclusion 

Hydrangeas are one of the rare species that change their colour over time, except for the white ones. This is purely due to scientific reasons. As the soil gets more acidic, hydrangeas turn blue, and if the soil is alkaline, you will witness a beautiful pink colour in your flowers. So, you can accordingly regulate the pH of your soil to see the desired changes in your flowers. You can also check the pH levels of your soil to avoid adding unnecessary products.

Suggested Reads :

• Simple trick to make your hydrangeas change colour
• How To: Change Hydrangea Color