- Soil with a pH lower than 5.5 will result in bright blue hydrangea flowers.
- When the pH is 5.5 to 6.5 the flowers will be an odd purple color.
- Soil with a pH higher than 6.5 will cause the flowers to be pink.
Why do hydrangeas turn blue?
Sometimes hydrangeas will change color over time as acidity levels in the soil change. Therefore, if you want to maintain the blue color of the flowers, you will need to monitor the pH level of the soil and take measures to preserve its acidity.
Will vinegar turn hydrangea blue?
There is one more trick up the apple cider vinegar sleeve: You can actually change the color of hydrangea flowers from pink to blue. Hydrangea flowers will be pink in alkaline soil, but change to blue in acidic soil. So, mix up some apple cider vinegar and water, and give all the acid-loving plants a treat. Read more.
What makes hydrangeas change color?
These are the steps you’ll need to take:
- Test the pH of your soil. You can do this with a home kit, an electronic soil tester from Amazon, or by sending it to your local extension office.
- Hydrangeas need soil acidity to be around 5.2–5.5 on the pH scale to produce blue flowers. ...
- Apply the S
How do pennies make hydrangeas blue?
Hydrangeas planted with pennies may display colorful blooms, but those pennies can't take credit for the color. Hydrangea flowers change color based on aluminum absorbed from the soil up into bloom tissue. Formed from copper-plated zinc, today's pennies do not contain any metals that influence hydrangea bloom color.
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What home remedy will turn my hydrangea blue?
If your hydrangeas are pink (meaning your soil is alkaline) and you want them to turn blue, make the soil more acidic by adding aluminum sulfate or a soil-acidifying treatment, which can be purchased at any garden center. Adding pine needles, compost, and even coffee grounds to the soil can help, too.
Will vinegar turn my hydrangeas blue?
There is one more trick up the apple cider vinegar sleeve: You can actually change the color of hydrangea flowers from pink to blue. Hydrangea flowers will be pink in alkaline soil, but change to blue in acidic soil. So, mix up some apple cider vinegar and water, and give all the acid-loving plants a treat.
Do coffee grounds make hydrangeas blue?
Some gardeners report success in turning their hydrangeas blue by applying coffee grounds to the soil. The coffee grounds make the soil more acidic, allowing the hydrangea to more easily absorb aluminum. In addition, fruit peels, lawn clippings, peat moss and pine needles, are thought to have a similar effect.
Can Epsom salt turn hydrangeas blue?
When the ions of Epsom salt disassociate, they have a neutral effect on the pH of the soil. Since the blue color of a hydrangea is formed by aluminum made available in acid soil, adding Epsom salt would not make your flowers change color.
Will baking soda change the color of hydrangeas?
Baking soda is alkaline, adding it to the soil will reduce acidity. To change hydrangeas blue, you want them to be more acidic, not less acidic. However, baking soda is a poor soil amendment. Even if you want to change flowers from blue to pink, baking soda wouldn't be the way to go.
How much baking soda do you put on hydrangeas?
A Little Goes a Long Way To apply it to your wilted hydrangeas, mix 1 tablespoon of baking soda into 2 quarts of water. Stir to be sure the baking soda thoroughly dissolves. Note: This amount treats 3-4 hydrangea bushes.
What is the best natural fertilizer for hydrangeas?
Animal manure is a good, balanced fertilizer for hydrangeas, and household compost is also a good addition to the soil under the plant.
What is best fertilizer for hydrangeas?
Typically hydrangeas thrive when fed an all-purpose, balanced fertilizer like a 10-10-10 N-P-K or 12-4-8 N-P-K. To increase the size and quantity of hydrangea blooms, consider a fertilizer with more phosphorus.
Is Epsom salt good for hydrangeas?
The short answer is yes it will – Epsom Salts is Magnesium sulfate and Sulfur is the mineral that we apply to the soil to lower the pH. You will also be applying Magnesium which should help enhance the color of your foliage since Magnesium is needed for chlorophyll production.
Do rusty nails turn hydrangeas blue?
A rusty nail changes the pH of soil so it is more acidic. This is why rusty nails, saw blades, tin cans or other forms of tin buried among the roots of the hydrangea shrub seem to change the color of the hydrangea to blue.
What do you put in the soil to keep hydrangeas blue?
Hydrangeas need two conditions to turn from pink to blue: they need an acid soil and aluminium or iron salts in the soil.
What do you put in the soil to change the color of hydrangeas?
Alkaline soil, with a pH above 7.0, promotes pinks and reds. With a pH between 6 and 7, the blooms turn purple or bluish-pink. To lower your pH, add garden sulfur or aluminum sulfate to your soil. To raise the pH, use ground lime.
Will vinegar harm hydrangeas?
Though vinegar can be fatal to many common plants, others, like rhododendrons, hydrangeas and gardenias, thrive on acidity which makes a bit of vinegar the best pick-me-up.
Does white vinegar help hydrangeas?
No, not really. The vinegar will quickly dilute in the soil, especially if it rains or is irrigated, not making much of a pH difference. Plus, for your hydrangeas to change colors, they need a pH change sustained over a long time.
How do you change purple hydrangeas to blue?
1:214:08How to change the color of hydrangea flowers. - YouTubeYouTubeStart of suggested clipEnd of suggested clipSo in order to make a pink hydrangea turn blue blue is signified by the amount of aluminum the plantMoreSo in order to make a pink hydrangea turn blue blue is signified by the amount of aluminum the plant can suck up and we just add some aluminum sulfate. Now this is aluminum sulfate right here. You can
How do I turn my blue hydrangea purple?
Generally speaking, acidic soil, with a pH lower than 6.0, yields blue or lavender-blue hydrangea blooms. Alkaline soil, with a pH above 7.0, promotes pinks and reds. With a pH between 6 and 7, the blooms turn purple or bluish-pink. To lower your pH, add garden sulfur or aluminum sulfate to your soil.
Does Epsom salt turn hydrangeas blue?
What does Epsom salt turn hydrangeas blue? Is it a real scientific question, or a silly story, a fairy tale, or just a myth? No matter what you call it, it’s an interesting fact, but is the idea true?
How long does it take to turn hydrangeas blue?
If you want to know how long does it take to turn hydrangeas blue, the answer is never.
Do coffee grounds make hydrangeas blue?
Do coffee grounds make hydrangeas blue? In truth, it does not matter how coffee you use or what kind of coffee you drink.
The Fastest Way to Turn Your Hydrangea Flowers Blue
If your hydrangea is in an area with other acid-loving plants, you can get straight to work with a soil acidifier amendment. An organic soil acidifier will adjust the pH of your soil over time. Soil acidifiers are usually a powder or granule applied on top of the soil and then watered in. Follow the application instructions on the package.
Concrete Can Affect the Color of Your Hydrangea
If your hydrangea is growing near a concrete driveway or sidewalk, you may have a more challenging time making the flowers change to, and stay, blue. This is because lime is commonly used as a binding ingredient in concrete. Lime raises the pH of nearby soil, making it more alkaline.
Community Q&A
My three formerly blue hydrangeas are planted with a tarp on the soil and small rocks and pebbles around them and other plants. Bricks were used as an edger. The complex uses a landscape service, and I'm not allowed to plant or remove things in the landscape. My hydrangeas were purchased blue. What can I do?
Tips
If you change your mind and want to turn blue hydrangeas back to pink, you'll need to incorporate dolomitic lime into the soil or use a fertilizer with high levels of phosphorus. Expect to do this regularly over the lifetime of the plant.
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All About the Chemistry
Because it's the soil chemistry that determines the bloom color, the variety names given to these types of hydrangeas means very little when it comes to bloom color. For instance, Nikko Blue, Pretty in Pink, Forever Pink and Blue Deckle, all have an almost equal chance of blooming pink or blue, depending on the soil they are planted in.
Conditions for Blue Hydrangeas
To encourage blue hydrangea flowers, grow the plant in soil that has a pH of 5.2-5.5. If your soil is more alkaline, you can lower the pH by applying Soil Acidifier at the rate specified on the package. Soil pH can also be lowered (more gradually) by applying an acidic organic mulch, such as pine needles or pine bark.
Conditions for Pink Hydrangeas
If you prefer pink blooms, your hydrangea should be deprived of aluminum by growing it in an alkaline soil with a pH of 6.0-6.2. You can apply a high-phosphorus fertilizer to further discourage the uptake of aluminum. To raise the pH of a naturally acidic soil, apply Garden Lime at the rate specified on the package.
How to Adjust the pH of Your Soil
Once you've tested the pH level of the soil where you intend to plant your hydrangea using a pH test kit, pH meter, or by submitting a soil sample to your local extension service, you'll have a baseline. If you are trying to maintain a certain pH level, you should test your soil each year.
1. Choose the Right Kind of Hydrangea
Only the flowers of bigleaf hydrangea ( Hydrangea macrophylla) can change color. Other types such as oakleaf hydrangeas or smooth hydrangeas such as 'Annabelle' only bloom in white or cream. These plants are just as full and beautiful, but if your goal is blue hydrangeas, make sure you're planting varieties that can turn the shade you want.
2. Choose Blue Varieties
Look for hydrangeas that are bred to be blue such as 'Nikko Blue', Endless Summer The Original, 'Penny Mac', 'Blauer Prinz', or Endless Summer Twist-n-Shout. The photo on the plant tag will help you choose blue-blooming varieties if the plants aren't in flower at the nursery.
3. Measure the Soil pH
Although doing this may sound like complicated chemistry, it's not. All soil has a pH value which measures the acidity or alkalinity. The pH scale is from 0 to 14; 7 is neutral. Soil pH values of less than 7 indicate degrees of acidity. Soil pH values greater than 7 indicate degrees of alkalinity.
4. Pick the Flower Hue You Want
For true blue flowers, the hydrangeas need to be grown in acidic soil with a pH of 5.5 or lower. For pink flowers, the plants need neutral to alkaline soils (pH 6.5 and higher). For purple blooms (or a mix of blue and pink flowers on the same plant), the pH of the soil must be between pH 5.5 and 6.5.
5. Adjust the Soil pH
Most garden soils tend to be neutral so you'll need to amp up the acidity to go blue. You can do that in a variety of ways. Organic acidifiers include sulfur and sulfate. There are also easy-to-use soil additives made specifically for hydrangeas.
6. Continue to Acidify the pH for Blue Blooms
Your soil pH likely will need regular adjustment to produce consistently blue blooms. Gently work acidifying soil additives into the top layer of the soil around the root zone whenever you'd normally fertilize your hydrangeas, usually in early spring.
What hydrangea colors are most common?
Above: Photograph by Sara Barrett for Gardenista. Hydrangea Serrata ‘Blue Billow’ is $34 from White Flower Farm.
What is used to test soil pH?
Next, place the soil sample in a container. Pour distilled white vinegar over it. If the solution fizzes, the pH level is high and your soil is alkaline. (If it doesn’t fizz, then the soil is neutral or acidic; you will not have to amend it as much to made your hydrangeas blue.)
How do you change soil pH for hydrangeas?
Add organic materials to your soil to make it more acidic. Coffee grounds are good. So is ground-up citrus peel. Work the mixture into the soil around the base of your hydrangea plant, and then water it in.
Lowering Soil pH with Coffee Grounds
Crushed egg shells will also increase the acidity of the soil. Work them into the ground along with citrus peel and coffee grounds.
