Some bigleaf hydrangeas (Hydrangea macrophylla) have the unusual capacity to switch from pink to blue, or vice versa, in the blossom color. The amount of aluminum in the soil that the plant can utilize has caused this alteration. Aluminum is easily accessible in acidic soils, and hydrangea roots can take this mineral in. However, plants are unable to absorb the element into their roots in alkaline soils. Your soil is too alkaline if you’ve ever planted a gorgeous blue hydrangea and the next year it blossomed pink.
Bigleaf hydrangeas can be made to change color by altering the pH of the soil, but only if they were pink or blue when they were first planted. Hydrangeas that are white will never change.
Get a soil test
Get a professional soil test, whether you plant in the ground or in containers, to determine the exact acidity or alkalinity of your potting mix or soil. You can purchase a home test kit or a pH meter from the garden center to obtain a pH measurement, albeit they are not quite as precise as a professional test (and you might not receive N-P-K levels). After that, you can appropriately adjust your soil to control the bigleaf hydrangea’s color.
How to get a professional soil test
You might be able to receive a referral to a lab where you can send a soil sample for an accurate test from your county extension office or nearby colleges. You can also visit this website to get a list of laboratories that conduct soil tests: Program for North American Proficiency (NAPT)
Can you alter a hydrangea’s color?
Lacecap and mophead hydrangeas (H. macrophyllas) can change color, unlike the majority of flowers. The first people to observe this were gardeners in the eighteenth century, who experimented by burying rusty nails, pouring tea around their plants, or even chanting spells.
Hydrangea Endless Summer ‘The Original’
While many gardeners, especially in hot regions, believe that hydrangeas require deep shadow, many actually enjoy early sun and afternoon shade. In zones 4 to 5a, with dappled afternoon shadow, Endless Summer hydrangeas are reblooming shrubs that like at least 6 hours of direct sunlight. The farther north you live, the more sun hydrangeas can tolerate.
However, whether or not the hydrangeas are absorbing aluminum from the soil is dependent on the pH of the soil, which also affects bloom color specifically. Aluminum is being given to the plant if the blossoms are pink. It’s not if they’re blue. By changing the pH, you can adjust the hue.
To find your pH, first use a soil test kit that you have purchased. Check with your local office to see whether they provide this service. You can also send a soil sample to several county extension agencies for testing.
Why did the color of my hydrangea change?
The pH of the soil affects the color of hydrangeas. While most other colors will change, white hydrangeas won’t. The color of the flowers will be pinker in more alkaline soil, while redder blossoms may occasionally appear in severely acidic soil. Your flowers will be bluer the more acidic the soil is.
Can white hydrangeas be dyed a different color?
Are hydrangea flower colors malleable? Your hydrangea’s kind and the pH of your soil will determine this. We’ll go over how to go from pink to blue or from blue to pink.
Which Hydrangeas Can Change Color?
Not all hydrangeas undergo color change. Some Bigleaf Hydrangeas (H. macrophylla), particularly the Mophead and Lacecap varieties and H. serrata cultivars, have flowers whose colors vary depending on the pH of the soil.
Pinks and reds thrive in alkaline or neutral soil, whereas blues grow best in acidic soil. In other words, pink flowers grow in soils with a pH higher than 6.0, whereas blue blooms grow in acidic soils with a pH lower than 5.5.
The pH of the soil has no impact on the color of white hydrangeas. The white flowers often prefer the same conditions as the pink and red blossoms because their color cannot be changed.
However, the connection between color and pH is more intricate than merely a scale of numbers. Color is influenced by the availability of aluminum ions and the extent to which a specific cultivar can absorb them.
How Long Does the Color Change Take?
It is possible, albeit not immediately, to change colors. For the necessary adjustments, color fixing can take weeks or even months. Some cultivars are more prone to color variability than others, and it is simpler to transform pink blooms into blue ones than blue blossoms into pink ones.
To give the plant enough time to recover from the trauma of its initial planting, we advise waiting until it is at least 2 years old.
Get the pH of your soil evaluated, then ask your neighborhood nursery for the recommended amount and application instructions of aluminum sulfate. Once a plant has had time to recover from the trauma of its first planting, you should follow these rules:
How to Change Hydrangea Color
With the knowledge of the aforementioned, it is relatively easy to raise acidity (for blue) or alkalinity (for pink):
To make flowers with darker blues more acidic: Apply a 14 ounce per gallon of water aluminum sulfate solution three times annually. (Sulfuric acid reacts with hydrated aluminum oxide to form the colorless compound known as aluminum sulfate. any garden center and purchase.) After the plant begins to grow in the spring, soak the ground with the solution and repeat twice at 3- to 4-week intervals. Apply 25-5-30 fertilizer as directed by the manufacturer once a year, in the spring.
To boost alkalinity (to turn blue blooms pink), distribute ground limestone (dolomitic lime) at a rate of 4 pounds per 100 square feet in the spring or fall and thoroughly water the area. (Excessive alkalinity will result in yellow leaves or chlorosis.) Apply 25-10-10 fertilizer as directed by the manufacturer in the spring or fall.
- In the fall, hydrangea flowers will naturally dry out and fade, frequently turning pink with green or tan. This is only the inevitable result of becoming older.
- Use rainwater to water your hydrangeas whenever feasible because hard water (water with a high mineral concentration) can also impact blossom color, turning blue flowers more reddish.
Why do hydrangeas turn pink or blue?
Blue hydrangeas were detested by my mother-in-law and disparaged as garish trailer park plants. In an attempt to kill the roots, she poured hot grease from her kitchen upon them, but it was ineffective. The blue blooms, which clashed with her magnificent golden euonymus and crimson artificial poinsettias, just kept coming.
Hydrangea Colors Changing She could have changed the color of her hydrangeas to a pink hue that looks much better with red fake poinsettias if she had known the method I’m about to share. She only needed to alter her soil; she didn’t need to change her mindset.
You see, the pH of the soil is indicated by the flower color of the majority of French hydrangeas (Hydrangea macrophylla). Flowers turn blue in soil that is extremely acidic (pH < 6). Flowers turn pink or even scarlet in alkaline soil (pH above 7). Purple or a combination of blue and pink blooms on a single shrub are possible on soil that is neutral or slightly acidic (pH 6 to 7). Remember that choices' sensitivity to pH varies. For instance, "Ami Pasquier" and "Purple Tiers" both maintain their color in all but the most acidic soil.
Do white hydrangeas count? I’m sorry, but they won’t cooperate. Regardless of the pH of the soil, they remain white.
Select a Hydrangea Color These six hydrangeas are among of our favorites and are frequently available. It can depend on your soil.
Except in extremely acidic soil, where it becomes a wine-purple color, “Ami Pasquier” has crimson blossoms. Lacecap design. ‘Ayesha’: The distinctive cupped petals attract the eye. pink to light blue in color. leaves with a lustrous deep green color. sort of mophead. Repeat blooming flowers on both old and new growth describe “Endless Summer.” possibly pink or blue. sort of mophead. “Madame Emile Mouillere”: Dedicated and tenacious. widely regarded as the finest white. May bloom again. sort of mophead. “Nikko Blue” is a dependable, hardy plant that has been commonly planted for a long time. soil that is alkaline turns pink. sort of mophead. Beautiful double-flowered lacecap variety called “Purple Tiers.” In acidic soil, water lily-shaped blossoms are a rich purple color; in alkaline soil, they are pink.
Making cut-flower hydrangeas It makes sense to want to cut the last French hydrangea blossoms because they are so lovely in the yard and may be displayed on your porch or brought inside. However, when the blossoms wilt an hour after being placed in water, it can drive you crazy. How can this be stopped?
How can I maintain a blue hydrangea?
Although most plants may grow in a variety of soils, others require particular kinds of soil to thrive. Rhododendrons, azaleas, and other ericaceous plants require acidic soils in order to thrive. The soil in your garden must be acidic if they flourish there or in the gardens nearby. Rhododendron leaves turning yellow or disappearing from the area indicate that your soil is likely alkaline. In addition to affecting what you may grow, your soil type can also affect some plants’ leaf and blossom colors; hydrangeas are a well-known example.
Some hydrangea cultivars grow pink or red in alkaline soil and blue or purple in acidic soil. Therefore, if you plant a beautiful blue lacecap or mophead hydrangea in your garden and your soil is neutral to acidic, it will continue to produce blue flowers every year. Even if it was clear blue when you got it, it will flower purple-red or pink if you plant it in alkaline soil the next year.
It is challenging to keep beautiful blue blossoms alive in the open ground, but it is doable if you grow it in a pot; hydrangeas make wonderful topics for pots and containers. Select a pot that is attractive and big, at least 40 cm (15 cm) in diameter. Vitax Ericaceous Compost is the best growing medium for it; plant it there. If you consistently feed your hydrangea, it will thrive on this fertilizer that is specifically made for rhododendrons, azaleas, and other lime-hating plants.
Even though the growing medium begins out being free of lime, repeated watering in places with hard water tends to make it more alkaline. Therefore, add Vitax Hydrangea Colourant, a powder containing aluminum that you may mix with the compost, to ensure that your hydrangea stays truly blue. Each spring, you can also incorporate a small amount into the soil’s top layer and add it to the can when watering your plant.
White hydrangeas, incidentally, don’t change color depending on the type of soil, but they can blush pink in the light.
Feeding and watering
In pots, containers, and during dry spells in the open ground, regular watering is necessary since hydrangeas detest dry environments. When you plant your hydrangea in a bed or border, add lots of garden compost or farmyard manure, and make sure to water well both before and after planting.
The presence of food in the soil is necessary for hydrangeas to grow and produce flowers, even if they are not very demanding plants. In the open ground and in pots and containers, Vitax Conifer and Shrub Fertilizer should be used annually. This is ideal for acid-loving plants and won’t change the hydrangea’s color.
What causes the white hydrangeas to turn green?
Blooms on green hydrangeas have a reason. Mother Nature, with a little assistance from the French gardeners who crossed the original Chinese hydrangea varieties. You see, those bright flowers aren’t even made of petals. They are sepals, the flower’s component that shields the flower bud. Why do green hydrangeas bloom? because the sepals naturally have that color. Colored hydrangea blossoms frequently turn green over time because as the sepals deteriorate, the pink, blue, or white pigments are swamped by the green.
Many gardeners think that the amount of aluminum in the soil is the only factor that affects color. You receive blue flowers from aluminum. Aluminum becomes pink when you bind it. Right? The narrative goes far deeper than that. With increasing daylight hours, the green hydrangea flowers begin to change color. Those colors are given the energy to dominate by light. Your hydrangea flowers may stay that hue for several weeks before turning green once more. The length of the days is reducing. The white, pink, and blue hues become less vibrant and disappear. Green hydrangea blossoms are in vogue once more.
Sometimes you can find hydrangeas with year-round green blossoms. You might have a variety called “Limelight” if you’re new to gardening or the plant is new to you and blooms later than its siblings. Despite having blooms that resemble mophead hydrangeas, these relatively new plants have considerably smaller leaves than the huge leaf types. This beauty’s flowers, which start and end in white but are bred to be green in between those times, change green naturally.
But if your hydrangea has green flowers and is one of the other varieties and the blooms won’t change, you’re the victim of one of Mother Nature’s sporadic tricks, and horticulturists have no idea why the condition exists. There has been no scientific explanation discovered, however it might be a mix of odd weather circumstances. Have courage. Only one or two seasons should pass before your green-flowered hydrangea recovers to normal health.
Why do green hydrangeas bloom? Why do green hydrangea blossoms occur? For the curious, they are intriguing questions, but are they ultimately relevant? If you notice the flowers on your hydrangeas turning green, take a seat, unwind, and take in the spectacle. Mother Nature is at her finest.
How much time does it take for hydrangeas to turn blue?
How is the pH of the soil altered? Add sulfur to make it more acidic. You add ground limestone, often known as lime, to make it more alkaline. Simple as pie, right? Wait a minute.
Some hydrangeas are quick to change color. One of them is the original “Endless Summer.” When I bought one that was blooming pink in the pot and placed it in my highly acidic soil, the plant produced bright-blue flowers the next year. Half of the flowers in a neighbor’s yard with nearly neutral soil were blue and half were pink.
Another issue is my “L.A. Dreamin'” hydrangea (see the picture above). It is also marketed under the name “Lindsey Anne,” which is the name of the breeder’s daughter. The first time I saw it in California, I fell in love. It was covered in large, multicolored blossoms in blue, purple, and pink. From early July to the end of the season, this 4-foot-tall shrub is in blossom. Additionally, it blooms on both old and new growth, so you can still obtain blooms on new stems even if cold destroys the flower buds or you prune at the incorrect time (in fall and winter).
In a large container, “L.A. Dreamin'” functioned admirably for me. The blossoms started off brilliant pink, grew over several months to almost redness. In the end, I dried the last of the blooms indoors. My only complaint is that I wanted a little bit more blue and purple.
I used Espoma Organic Soil Acidifier, which is safer than possibly hazardous aluminum sulfate and includes 30% sulfur. According to the package, you should scatter 1 1/4 cups or 2 1/2 cups of fertilizer around each new plant. For every 4 inches of pot diameter, a tablespoon is given to plants in containers. Water it in after evenly distributing the sulfur to the widest branches. Repeat until you achieve the desired hue at intervals of 60 days. Blooms that are violet-blue should appear at a pH of 5.5, whereas deep blue blooms will do so at a pH of 4.5. Flowers bloom in a more subdued blue at a soil pH of 5.0.