How To Change The Color Of Hydrangeas With Aluminum Sulfate

Hydrangeas are fascinating in that, unlike most other plants, the color of their flowers can change dramatically.

It would be nice if one could change the color of hydrangeas easily. But for most of us, it is not easy. The people who have the most control over the color of their hydrangeas are those who grow them in containers. It is much easier to control or alter the pH of the soil in a container than it is in the ground.

On the other hand, hydrangeas often change color on their own when they are planted or transplanted. They are adjusting to the new environment. It is not unusual to see several different colors on one shrub the next year after planting.

It is much easier to change a hydrangea from pink to blue than it is from blue to pink. Changing a hydrangea from pink to blue entails adding aluminum to the soil.

Changing from blue to pink means subtracting aluminum from the soil or taking it out of reach of the hydrangea. This can be achieved by first treating the soil with a phosphorous based fertilizer followed by a treatment of lime or calcium. the pH should be raised to 6.0 to 6.5 but never higher than this.

In order to change the flowers of the hydrangea from pink to blue there needs to be aluminium present in the soil and a pH of less than 7 ideally between 5.2 and 5.5 (Acidic). Only plants older than 2 years which are established should be treated. Before commencing treatment to change colour it is strongly advisable to water plants thoroughly every day for a week. Where possible test soil around hydrangeas for pH.

Add 15g (1 tablespoon) of aluminium sulphate in a litre of warm water and allow to sit for 15-30 minutes to dissolve. Add this to a watering can and make up to 5 litres with cold water. Apply the solution around the based of the hydrangea. DO NOT OVERUSE as making the soil too acidic can result in damage to the roots. Check the pH and maintain it between 5.2 and 5.5. Other simple things you can do include adding as grass clippings, coffee grounds and fruit or vegetable peelings to help lower pH levels. Potassium rich fertilizers will also help to achiev this.

Where to Buy Aluminum Sulphate online UK

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How to reduce pH of soil with aluminium sulphate

SOIL pH – WHAT IS IT ?

The pH scale is simply a mesurement of the level of acidity. The pH scale is 1 to 14 and is nomally viewed in 3 sections: pH1 to pH6.9 is ACID, pH7 is NEUTRAL and pH7.1 to pH14 is ALKALINE (or BASIC).

Most plants prefer a slightly acidic soil between pH6 and pH6.8 and some plants like rhododendrons, azaleas and bluberries thrive in more acidic soils around a pH5 to pH5.5.

HOW TO REDUCE SOIL PH WITH ALUMINIUM SULPHATE

The aluminium sulphate should be applied to the garden as a liquid to realise a fast change in the pH. Before starting you need to know the pH of your soil. This can easily be done using a soil testing kit you can buy in any good garden centre or with a pH meter. As a rule of thumb to reduce the pH by 1 point you need to apply 50g of aluminium sulphate for every square metre of soil.

Example: if your soil pH is 7.5 and you want to reduce it to pH6.5 and you have an area of 30 square metres then you will need 50×30 = 1500g of aluminium sulphate.

Ideally the aluminium sulphate needs to penetrate into the soil to be effective or you will be just acidifying the surface. One suggestion to aid penetration would be to spike the garden as you go along. For every 5 square metres of garden you need to apply 250g of the aluminium sulphate. Dissolve this in a litre of hot water by leaving it to sit for 15–30 minutes. Add to a watering can and top up with cold water. Apply this to the 5 sq m of garden. Repeat the process for each 5 sq m to be treated.

Alternatively you could dig it into the soil again at a rate of 50g per square metre but this will take a lot longer to be effective as the sulphate is slow to dissolve.

Where to buy aluminium sulphate online in UK

HOW TO CHANGE HYDRANGEAS FROM PINK TO BLUE

Hydrangeas are fascinating in that, unlike most other plants, the color of their flowers can change dramatically.

It would be nice if one could change the color of hydrangeas easily. But for most of us, it is not easy. The people who have the most control over the color of their hydrangeas are those who grow them in containers. It is much easier to control or alter the pH of the soil in a container than it is in the ground.

In order to change the flowers of the hydrangea from pink to blue there needs to be aluminium present in the soil and a pH of less than 7 ideally between 5.2 and 5.5 (Acidic). Only plants older than 2 years which are established should be treated. Before commencing treatment to change colour it is strongly advisable to water plants thoroughly every day for a week. Where possible test soil around hydrangeas for pH.

Add 15g (1 tablespoon) of aluminium sulphate in a litre of warm water and allow to sit for 15-30 minutes to dissolve. Add this to a watering can and make up to 5 litres with cold water. Apply the solution around the based of the hydrangea. DO NOT OVERUSE as making the soil too acidic can result in damage to the roots. Check the pH and maintain it between 5.2 and 5.5.

Where to buy aluminium sulphate online in UK

How To Change The Colour Of A Hydrangea Plant With Aluminum Sulphate

Hydrangeas are fascinating in that, unlike most other plants, the color of their flowers can change dramatically.

It would be nice if one could change the color of hydrangeas easily. But for most of us, it is not easy. The people who have the most control over the color of their hydrangeas are those who grow them in containers. It is much easier to control or alter the pH of the soil in a container than it is in the ground.

On the other hand, hydrangeas often change color on their own when they are planted or transplanted. They are adjusting to the new environment. It is not unusual to see several different colors on one shrub the next year after planting.

It is much easier to change a hydrangea from pink to blue than it is from blue to pink. Changing a hydrangea from pink to blue entails adding aluminum to the soil.

Changing from blue to pink means subtracting aluminum from the soil or taking it out of reach of the hydrangea. This can be achieved by first treating the soil with a phosphorous based fertilizer followed by a treatment of lime or calcium. the pH should be raised to 6.0 to 6.5 but never higher than this.

That said, I’ll give the best information that I have on this subject and let you take it from there.

In order to change the flowers of the hydrangea from pink to blue there needs to be aluminium present in the soil and a pH of less than 7 ideally between 5.2 and 5.5 (Acidic). Only plants older than 2 years which are established should be treated. Before commencing treatment to change colour it is strongly advisable to water plants thoroughly every day for a week. Where possible test soil around hydrangeas for pH.

Add 15g (1 tablespoon) of aluminium sulphate in a litre of warm water and allow to sit for 15-30 minutes to dissolve. Add this to a watering can and make up to 5 litres with cold water. Apply the solution around the based of the hydrangea. DO NOT OVERUSE as making the soil too acidic can result in damage to the roots. Check the pH and maintain it between 5.2 and 5.5. Other simple things you can do include adding as grass clippings, coffee grounds and fruit or vegetable peelings to help lower pH levels. Potassium rich fertilizers will also help to achiev this.

Where to Buy Aluminum Sulphate online UK