The sought-after vibrant blue to purple flowers will be produced by high soil aluminum concentrations combined with an acidic soil pH. A variety of pink blooms will appear depending on whether the soil is alkaline or contains less aluminum. However, not all hydrangea species exhibit color variation. White variations remain the same, while others are bred to have a particular color scheme.
Before you get too excited, keep in mind that you cannot alter the hydrangea’s color intensity; it is more influenced by the surroundings or the weather. However, I have to admit that it is really thrilling to see the hydrangea bloom color change so radically!
Soil Test
Checking the pH of your soil is the first thing you should do. Pink flowers grow in alkaline soil, which has a higher pH, whereas blue blooms grow in acidic soil, which has a lower pH. You can purchase a soil test kit at your neighborhood garden center to ascertain the pH of the soil, but there is a quick and easy way to do it using items from your kitchen.
To get pink or blue hydrangea flowers, you can modify the pH of your soil once you know what it generally is.
Changing the Colour of Hydrangea Flowers to Blue
If your soil is alkaline and your hydrangeas are pink instead of blue, you must add more aluminum to the soil to make it more acidic.
To do this, amend your soil with things like pine needles, compost, coffee grounds, elemental sulphur, and gypsum, or feed your plants with an organic fertilizer containing cottonseed meal.
Adding aluminum sulphate to the soil is frequently not essential and may even be detrimental. Aluminum is abundant, not a necessary plant nutrient, and can be hazardous in large quantities.
Remember that altering the pH of your soil is a slow process, so don’t expect bright blue blooms right away. The color change may not occur for up to a year.
If your soil is naturally alkaline, adding an aluminum source will be necessary to maintain their blue color throughout the growth season. Sulfur is one of the most often used additives. Add 1/2 cup of sulfur per 10 square feet to utilize it. Every three months, repeat the procedure.
Changing the Colour of Hydrangea Flowers to Pink
You must remove the aluminum from the soil in order to convert blue hydrangea flowers to pink ones. The only method to accomplish this is to elevate the pH of the soil by adding garden lime.
Garden lime, a slow-release supplement for treating acidic soil, is crushed limestone rock. It has calcium carbonate in it, adding calcium while also bringing the pH of the soil up.
For every 10 square feet, sprinkle 1/2 cup of garden lime. Again, to maintain pink blossoms throughout the growth season, lime must be added every two months.
How do I achieve a pink bloom on my hydrangea?
How many of you can recall the argument between the fairy godmothers in Walt Disney’s Sleeping Beauty about the color of the princess’ ballgown? Every time the traditional mophead hydrangeas (Hydrangea macrophylla) bloom in June, I recall that scene. The colors are the stuff of enchantment because they are so vibrant.
Aluminum, not a fairy godmother, controls the color of this hydrangea’s blossoms, whether they are pink or blue. Lack of metal results in pink blossoms, whereas an abundance of aluminum results in blue flowers.
For pink blooms, add lime to the soil; for blue blooms, add aluminum sulfate. The soil composition determines the required amount of lime or aluminum sulfate.
If you are adamant that your hydrangea will be pink or blue, plant it in a container where the pH of the soil may be easily controlled.
Can you dye hydrangeas pink with vinegar?
Although vinegar has a place in the home, does the garden need it as well? In order to alter the color of the blooms on bigleaf hydrangeas (Hydrangea macrophylla), some gardeners have begun using vinegar to lower the pH of their soil. Does this really function? The simple answer is, sort of; theoretically, it could. But is it the most effective long-term remedy for changing the pH of your soil? Here’s why we don’t believe it!
A Quick Chemistry Lesson
Did you know that the bloom color of hydrangeas isn’t directly influenced by the pH of the soil? It becomes a little trickier than that! In reality, bloom pigments are reliant on the presence of aluminum ions (Al+) in the soil. Aluminum ions react with hydroxide ions (OH-) in basic soils (pH > 7.5) to generate Al(OH)3, which is stationary in the soil and unavailable to plants. However, these aluminum ions are no longer bound by hydroxide and are free to mix with other ions when the soil becomes more acidic (pH lower than 6.5). Other ions, particularly those that plants absorb, will react with it. Aluminum is now “mobile” and available for plant uptake as a result. Hydrangea blossoms turn blue as they absorb more aluminum ions. Bigleaf hydrangeas can produce pink or blue flowers depending on whether the soil is acidic or basic.
While increasing the mobility of aluminum in your soil will alter the color of your blooms, it can also be harmful to your plants. A poisonous soil can have a pH that is too low. The plant may even perish if there is too much aluminum in the soil. To make sure you are not reducing the pH too much, make sure you test your soil frequently.
What does this have to do with vinegar?
Acetic acid, which makes up 5% of vinegar, is an acidic mixture of water. Since home vinegar has a pH of about 2.4, it is neutral at a pH of 7. (which is quite acidic). According to the hypothesis, adding weak vinegar to the soil will cause the pH to decrease sufficiently to alter the color of your hydrangea blossoms. The soil will become more acidic thanks to this tactic, but only temporarily.
Do we consider this to be a viable option? Not really, no. If it rains or is watered, the vinegar will quickly dissolve in the soil and have little effect on pH. Additionally, hydrangeas require a pH adjustment that is sustained over a lengthy period of time in order to change color. It might require more time than a single growing season! To keep the pH stable, you would need to add vinegar to the soil each time you water.
The greatest option for your plant or the surrounding wildlife may not be this one. You may have heard that vinegar can be used to destroy weeds. Any leafy green tissue that vinegar is sprayed on will be destroyed because the acetic acid in vinegar can quickly burn through the wax layer on leaves. When sprayed directly to the soil, the vinegar doesn’t hurt the roots. Pests like fungus gnats will be attracted to the vinegar’s pungent fragrance, while wildlife will be deterred from making your garden their home. Even worms and other significant soil creatures that are advantageous to your garden can be discouraged by it!
What are the alternatives?
Personally, we don’t advocate changing the pH of your soil because we believe hydrangea blossoms are lovely in every color. In the garden, a pH change can have a variety of effects, including making the soil unsuitable for neighboring plants. If you’re set on changing your bloom color, we advise using ground lime to raise pH levels or garden sulfur or ammonium sulfate to drop pH levels. Consider planting your shrub in a sizable pot because doing so is simplest in a container.
How much baking soda is required to turn hydrangeas pink?
Ever wondered what happened to your hydrangeas after going outside to check on them? They frequently appear unexpectedly exhausted and wilting, as if they are close to passing away. Your hydrangeas might even appear to get smaller every year. Here’s how to restore hydrangeas and make them seem gorgeous once more!
Everyday Care of Hydrangeas
Make sure you are familiar with the ideal hydrangea daily maintenance. Both location and a nutrient-rich, well-drained soil are quite important. Never overwater them, and don’t fertilize them too frequently. Read my entire post to learn how to take care of hydrangeas. Get ready for the next phase once you have a firm handle on how to care for your hydrangea plants on a daily basis!
The Secret to Revive Hydrangeas
Your hydrangea bushes can be revived with a top-secret chemical, but I’m going to tell you what it is! Although you’ve probably never heard of it, you already have the secret ingredient in your kitchen. Have you prepared? It’s baking soda, of course!
A Little Goes a Long Way
The key is baking soda, but be aware that a little goes a long way. Mix 1 tablespoon of baking soda with 2 cups of water and use it to revive your hydrangeas that have withered. Make sure the baking soda completely dissolves by stirring. Note: This dose is sufficient for 3–4 hydrangea shrubs.
Every two weeks, apply this baking soda treatment. If you only have one hydrangea plant, you can apply the therapy to other weak plants and still get similar results.
Enjoy Thriving Hydrangeas!
You should start to notice more strong hydrangeas in a week or two. The plants start to produce flowers that are fuller and healthier.
Try baking soda if your hydrangeas just aren’t impressing you like they should. Try baking soda in the rest of your garden while you’re at it as well!
Note from the editor: This article was first published in July 2017. The information has been revised.
How can I make my hydrangeas purple or pink?
This traditional favorite is a must-have in any garden, and new cultivars have made hydrangea cultivation simpler than ever.
Generally speaking, blue or lavender-blue hydrangea flowers are produced by acidic soil, which has a pH lower than 6.0. Pinks and reds are encouraged by alkaline soil, which has a pH above 7.0. The blossoms turn purple or bluish-pink at a pH of 6 to 7.
Add aluminum sulfate or garden sulfur to your soil to reduce pH levels. Use ground lime to increase the pH. To ensure that the pH of your soil is within the desired range, retest it according to the instructions on the product you’re using.
Pink hydrangeas: How do you keep them pink?
ASK THE SPECIALIST:
I’ve never tried to grow hydrangeas in pots before, and they’re actually doing rather nicely. My first plant, which I purchased in April, was purple; it is now more of a greenish color (very beautiful color). I also have burgundy and a pale pink shade called “white spirit.” How can I preserve the hues of blue, pink, or purple? What kind of plant fertilizer works best, and anything else that would keep my potted hydrangeas looking lovely. I appreciate your assistance in this case. -Juanita
The hydrangeas will eventually require replanting in the ground. You must have Mophead hydrangeas, I’m assuming (Hydrangea macrophylla). The pH of the soil, in particular, affects the bloom colors of certain varieties of hydrangeas.
- You would add lime to the soil amendment process to preserve hydrangeas pink.
- You would apply aluminum sulfate to keep it blue.
- A more neutral soil pH usually leads to purple blooms.
Once a bloom has developed, the color cannot be altered or controlled. Therefore, there is nothing you need to do at this time. However, the hue may shift to a paler pink or blue when the bloom starts to fade (which they all do). Towards the conclusion of the bloom life, certain cultivars will transition to a light greenish or dusty pink hue.
Feed them with a slow-release fertilizer once or twice during the course of the summer. Something with a balancing ratio of 10-10-10 or 14-14-14 is what I advise. This product is available in your nearby nursery and garden center.
I hope you found this information useful. If you require assistance with anything else, kindly let me know. Consult an expert Reply: Jamie, Thank you for responding. Macrophylla hydrangeas are what I have. I’m unable to plant them in the ground. They have to remain in pots because I live in an apartment building. They are now little, but as they grow, I will plant them in bigger pots until they are no longer manageable. I’ll give them away after that and start afresh. I have two greenish-colored hydrangeas. When should I remove the blooms? I hate to cut them because they are so gorgeous and healthy, but I must if I want more flowers in the spring. Please tell me the brand names of the fertilizer and aluminum sulfate you suggested—10-10-10 or 14-14-14.
I’m having difficulties getting plant food for my herbs, which I also have growing. These include basil, thyme, flat leaf parsley, rosemary, onions, and chives. I can only manage to find plants that are blended for both food and flowers. I don’t want chemicals in the plant food; could you kindly suggest a brand? I appreciate your support. Plant Expert at Flower Shop Network Reply: The blooms don’t need to be removed until they are entirely wasted. The blossoms on hydrangeas last for a very long time, which is great. You have two fertilizer alternatives if you are maintaining your plant in a pot: water soluble and slow release granular.
I enjoy using Peters or Hi-yield water soluble fertilizer. Osmocote is a slow-release granular that I prefer to use. These goods are available at your neighborhood nursery or garden center. I take it that by “chemicals” you mean an insecticide or fungicide when you say you don’t want them in your fertilizer. These kinds of chemicals won’t be present in any of these fertilizers.
What are pink hydrangeas fed?
Once you understand a few fundamental principles, caring for and feeding hydrangeas is fairly easy. Although it is offered, specialized hydrangea fertilizer is not truly required. All the fertilizing hydrangeas require is an excellent all-purpose 12-4-8 or 10-10-10 formulation. It is possible to use either a chemical source or organic material successfully.
The easiest way to care for and feed hydrangeas is to use a once-per-year slow-release fertilizer designed for shrubs and trees. It will also function with a less expensive fast-release substance. Sulfur, compost, and peat moss are effective hydrangea fertilizers, according to research on how to naturally fertilize hydrangeas.
Vinegar can I spray on hydrangeas?
Some common plants, like rhododendrons, hydrangeas, and gardenias, thrive on acidity, making a little vinegar the greatest pick-me-up. However, vinegar can be lethal to many common plants. The next time you water these plants, mix one cup of unflavored white vinegar with a gallon of water to get fantastic results. For plants that don’t like acidity as much, you may also add some distilled vinegar to your soil to combat lime or hard water.