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How To Keep Hydrangeas Pink: The Secret is in the Soil

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Hydrangeas are among the most popular flowering shrubs for home landscapes because they’re easy to grow, tolerant of a wide variety of soils, and provide a profusion of colorful blooms throughout the growing season.

Hybrids are the most common varieties grown today; however, hundreds of cultivars are available, ranging in height from about 2 feet to over 8 feet tall.

Some are single-stemmed, while others form dense clumps of branches. Most hydrangeas bear showy clusters of blue, white, pink, and green flowers.

The soil’s pH level directly affects the color of the Hydrangeas color, and this article will explain exactly how hydrangeas flowers can maintain their color and what you can do to help.

How To Keep Hydrangeas Pink

how to keep hydrangeas pink

Hydrangea flowers come in colors, from white to blue, pink, and purple. Some people prefer one color over another, but most admire them for their beautiful blooms.

Hydrangeas are an interesting type of plant whose color changes depending on the pH of the soil that they are grown.

Changes in soil content ions, organic material, and pH will cause Hydrangeas to change color.

A study found that the color variations in hydrangeas depend on the soil’s aluminum concentration and pH levels.

Blue hydrangeas are grown in soils rich in aluminum, while pink hydrangeas grow in acidic soils.

Aluminum is a trace element that helps plants absorb nutrients such as phosphorus, potassium, magnesium, calcium, zinc, iron, copper, manganese, molybdenum, boron, and chlorine.

How Do Hydrangeas Keep Their Colors?

Hydrangeas will change color depending on the pH of the soil

Hydrangeas will tend to keep their colors only if the quality of the soil does not drastically change. However, soil, as we know it, will change over time:

  • As the plant uses nutrients
  • When it is watered, 
  • When it’s exposed to the natural environment.

As a result, you will have to make the necessary additions to the soil to keep it in a “pH state” that will prompt the plant to remain in the color that it’s in.

Note: Hydrangeas Take Their Time

I’ve been growing hydrangeas since 1989. They’re one of my favorite perennials because they don’t require much care, and they come up every spring.

There are many things to consider when choosing a plant for your garden. One of the most important factors is how long it takes to flower. Some varieties flower quickly, while others take several seasons.

If you notice buds forming on the ends of branches, that’s a good sign that the plant is ready to bloom. When the buds open, you know you’re close.

After the initial fertilization, you’ll probably see little changes over the course of the season. You may even see some flowers changing colors. Don’t worry; that’s normal. Just keep watching.

If you’re looking for a specific shade of pink, try ‘Fernwood Rose.’ Its bright red center makes a beautiful contrast against the pale pink petals.

How to Change the Colour of a Hydrangea

keep hydrangeas pink

Hydrangeas come in many different colors. But how do you go about changing the colour of one? Well, it turns out that there are a few ways to achieve this, depending on what type of hydrangea you have.

If you want to make your hydrangea something new, here are three methods you can try.

Note: These methods help change the pH of the soil, so it’s important to check the pH changes closely.

Change the Soil’s Alkalinity

Alkalinity refers to the amount of acidity in the soil, and it plays an important role in determining the color of the hydrangeas. As we mentioned earlier, less aluminum in the soil and more calcium mean a darker shade of pink.

Increase Low Soil pH

The best way to increase the alkalinity of the soil is by adding lime to the soil. This helps neutralize any acidic elements present in the soil.

You should also be aware that certain hydrangeas prefer slightly acidic soil, so you might need to adjust the pH level accordingly.

To Lower Soil pH

Lower soil pH by adding elemental sulfur, aluminum sulfate, or phosphorous-based fertilizer. These two elements help lower the pH of the soil.

The choice of which material to use depends on how fast you hope the pH will change and the type/size of the plant experiencing the deficiency.

It is important to monitor the changes in soil pH as the above-mentioned additives are used to ensure that you are not overdosing, which will eventually lead to the death of the plant.

Add Fertilizer

Fertilize your hydrangeas regularly. Use a fertilizer that is specifically designed for houseplants.

A good rule of thumb is to apply half the recommended amount once a month and the rest twice a month. For example, if the package recommends applying 3 teaspoons of fertilizer monthly, you should spread those doses over three applications.

Fertilizing too frequently might cause your hydrangeas to grow lushly, but it could also stunt the growth of the stems.

Inorganic Fertilizer

A general-purpose plant food containing all four major nutrients (nitrogen, phosphorus, potassium and magnesium) is usually sufficient.

Organic Fertilizer

Use organic fertilizer such as manure from composted or aged cattle dung or chicken poop.

Manure contains nitrogen, phosphorus, and potassium, all essential nutrients for plants. It’s recommended to apply manure at least once per year.

Organic fertilizers are made from natural sources such as manure or composted animal waste. They contain nutrients like nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, copper, zinc, iron, manganese, and others.

These nutrients help plants grow better and reduce soil erosion and pollution.

Add Aluminum

Adding aluminum to the soil is another method that works well with all types of hydrangea. It’s especially effective at increasing the color intensity of blue hydrangeas.

However, it’s important to note that aluminum can cause toxicity problems if used incorrectly. If you decide to add aluminum to your soil, use caution and follow the instructions carefully.

Changing the Environment

If you live where the temperature is consistently warm, like Florida, California or Texas, you might want to consider growing hydrangea in those areas.

These plants love warmer temperatures, so they will most likely produce a brighter shade of color.

If you live in a colder area, such as Canada or New England, you might want to look towards planting a hydrangea near a south-facing window or balcony.

This way, you can enjoy the sun during the day while having the plant provide you with colorful blossoms throughout the night.

How to Determine the soil pH Level

Indicator Method

To measure soil pH you can use a test kit or a simple pH meter. You need to take a sample of your soil (about 1/4 cup) and put it into a glass jar.

Add water until the soil is moistened. Then add a few drops of indicator solution to the soil and shake the jar well.

The indicator turns the color of the water off if the pH is too high or low. If the color remains unchanged, then the soil has a neutral pH.

Soil Test Kit

A soil test kit measures the acidity or alkalinity of the soil. It consists of a plastic tube containing two chemicals: one which turns red when exposed to acids and one which turns blue when exposed to bases.

The soil is mixed with water and placed in the tube. A small amount of the mixture is poured onto a piece of paper and allowed to dry.

When the paper becomes completely dry, the results of the test are read by comparing the color of the paper with the chart provided with the kit.

pH Meter

A pH meter is a small device inserted into the soil, which then indicates the soil’s pH via a gauge on its display. They come in both digital and analog (dial) formats.

For keeping my soil at the perfect moisture levels I use this soil moisture meter. It is both cost-effective and durable. Best of all, it also measures pH and light.

digital soil moisture meter

Tips Keep Your Hydrangeas Healthy

Hydrangeas are easy to grow, but they still require regular attention. Here are some tips to help ensure healthy growth and vibrant blooms.

Water regularly. The key to keeping hydrangeas happy is water! Watering them regularly throughout the summer months will encourage strong stems and leaves.

Feed them once or twice during the growing season. Fertilizing plants encourages healthy growth and flowering. However, too much fertilizer can lead to nutrient deficiencies.

Mulch around the base of the plant. Mulching keeps weeds under control, which means fewer pests and healthier roots.

Don’t let your hydrangeas get too dry. Drought stress leads to wilting and brown foliage. To avoid this problem, water your plants thoroughly before the first frost.

Use these tips to keep your hydrangeas healthy and colorful. And don’t forget to enjoy their beauty as soon as they start to bloom.

How To Keep Hydrangeas Pink Naturally?

To Keep Hydrangeas Pink, Naturally, sprinkle some baking soda around the base of each plant once a week this helps to preserve the color for some time.

This helps to balance out the acidity in the soil, making it easier for the plant to absorb nutrients and water.

Just make sure you use baking soda sparingly; too much of it can cause harm to the roots of the plant.

You’ll want to keep the soil pH level high enough to support plant growth. If you don’t know how to test the soil’s pH level, please refer to our article about how to measure the soil’s pH level.

Once the soil pH level reaches 7.5, you can stop adding baking soda. However, if you notice that the soil pH level drops below 5.0, you’ll need to start sprinkling baking soda again.

Can White Hydrangeas Turn Pink or Blue?

Hydrangea flowers come in three colors: white, blue, and pink. Hydrangea flowers usually turn from green to pink to red when ready to bloom.

White hydrangeas, however, don’t change color until they’ve finished blooming.

They aren’t as sensitive to the pH of the soil compared to the other colors.

The only time White  Hydrangeas begin to change color is when the blossom is growing old and dying. Here, the blossoms will turn pink, tan, or blue, depending on the genetics of the flower itself.

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