Popular flowering garden shrubs like hydrangeas regularly confound us by altering the color of their flowers after they have been planted. And since the color change is probably a slow process, it can take a few years before you notice it has happened.
Can the color be changed back? is one of the first queries that a new student or client for landscape design makes. Is the hydrangea in trouble? is a different issue.
Will my Hydrangea die if it changes colour?
If the only problem is the color change of the blue to pink or pink and purple to blue blossoms, it is doubtful that your hydrangea is dying. Hydrangeas are often simple plants to maintain. As we’ll see below, your Hydrangea’s color change could have underlying factors that could ultimately harm the shrub’s general health.
Why has my Blue Hydrangea turned Pink?
After being brought home and planted in the garden, not all hydrangea varieties will change the color of their flowers. The soil determines whether they do.
The bushes that are most frequently seen in gardens are hydrangea macrophylla, also referred to as mop-head hydrangeas. Due to the rounded flower balls on them, they are known as mop heads. Lace cap hydrangeas, in contrast, have smaller, fertile flowers that are encircled by bigger, sterile sepals.
These two hydrangea kinds will almost certainly change color depending on the pH of your soil. With a pH meter or test kit from a garden center, you can quickly determine how acidic or alkaline your garden soil is. Also see the blogs listed below.
The impact this has on the levels of aluminum in the soil, rather than just the acidity of the soil, is the real cause. Aluminum levels rise with soil acidity, turning pink and purple hydrangeas blue as a result. The blue flowered should persist on soil with a pH of 6 or lower.
If you want to be sure of retaining the blossom color, the tip is to check the soil pH before you buy a mop-head or lace cap Hydrangea.
How do I Keep my Blue Hydrangea Blue?
Alternately, place your mop-head hydrangeas in a peat-free ericaceous compost-filled ericaceous bed. Rhododendrons, azaleas, and your hydrangeas might all be planted together. A floral display from April to October can be expected if you group all the acid-loving plants together.
How do I Keep my Pink Hydrangea Pink?
by having soil that is alkaline, or has a pH of 7 or above. An acceptable pH range of 6.57 should be achieved; cover with compost made from used mushrooms to help keep the soil alkaline.
Why not grow your hydrangeas in containers if your soil is acidic? One on each side of your entrance door might look really attractive.
What about my Purple flowered Hydrangea?
A good query! I’m not sure I can readily respond to that question because it depends not just on the soil but also on the shrub’s ancestry. Because of this, some purple hydrangea blossoms do not turn pink when planted in acidic soil.
Why has my Blue Hydrangea turned PinkMore Solutions to the Problem
Why not buy a Hydrangea that won’t change color when planted to make your life easy from the start? Not all hydrangeas exhibit the same tendency for blossom color change.
For instance, even in macrophylla cultivars, white and green flowering variations have a tendency to remain the same color.
Hydrangea petiolaris
Likewise called the climbing hydrangea. It is a robust, self-clinging climbing shrub that is cultivated for its heads of white flowers.
It takes time to establish itself, but once it does, it can grow vigorously and may need to be pruned if you don’t want it to cling to your gutters!
Dark green foliage changes to butter yellow in the fall before wintering as a tracery of branches. The young twigs have a lovely reddish brown sheen.
HydrangeaPruning Tips
It’s not just about the reason why your blue hydrangea turned pink, of course. You could be perplexed as to why there aren’t any flowers at all despite pruning the bush.
Although hydrangeas don’t need much trimming, adopting a strategy that promotes new wood will keep them from being too woody. Continue reading to make sure you pruned your shrub correctly for its type.
Between February and early March, you can prune a lot of summer-flowering deciduous shrubs, typically those that bloom on the growth of the current year. One hydrangea that has to be pruned frequently is hydrangea paniculata.
On the wood from the previous year, mop-head hydrangeas bloom. If you live in a mild climate, you can deadhead by cutting back to a strong pair of shoots as early as late February, or you can wait until March.
What next?
Now that we know the reason why the blue hydrangea turned pink, we can determine which blossom colors are still the same as when you first acquired the plant.
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Gardens to visit with Hydrangeas
The Holehird Gardens, home of the Lakeland Horticultural Society, includes a Hydrangea walk with more than 300 species if you’d like to take in hydrangeas in their entirety. In July and August, this is the place to go if you’re still not convinced about the beauty of hydrangeas because you’re likely to locate one for your own yard. Check out a description of one of my visits in the list of blogs below.
Even though they don’t have the same diversity of species as those available at Holehird, other locations of the UK with acidic soil frequently have attractive displays of hydrangeas. One particularly evocative example is the shady drive at Portmeirion, which has lighting Hydrangea plants tracing your path. There are more gardens worth seeing on the west coast of Scotland, in Ireland, and in Cornwall.
Visit Plews Potting Shed blogs, such as the ones below and our monthly Tipsheet, for additional gardening guidance and inspiration.
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How are blue hydrangeas kept that color?
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.
How can I restore the color of my hydrangea?
The chemistry of the soil, not what is sprayed to the blooms, is what determines how colored hydrangea blossoms turn out to be. The color of the blossoms will increase with soil alkalinity. Some types stay pink at a neutral pH, while others begin to display exquisite lavender hues with undertones of blue. Acidic soils, usually with a pH of 5.5 or less, are ideal for blue hydrangea blooming.
Aluminum sulfate, which is readily accessible at practically any garden center, is the simplest way to acidify your soil and turn those babies blue. In the spring, as soon as the plant starts to grow, saturate the soil around your hydrangeas with a solution of 1/4 oz. aluminum sulfate in a gallon of water. Reapply in 4 weeks and again in 8 weeks because you’ll need to keep that acidity throughout the growing season.
Another, more organic way to increase soil acidity is to add organic materials like coffee grounds, egg shells, or citrus fruit peels. Simply break them up and till the soil with them. It can take a full year of doing this continuously for the changes to occur gradually, resulting in the proper acidity.
How can hydrangeas be prevented from turning pink?
Large-leaved hydrangeas are stunning flowers with a wide range of hues, including vivid blues, purples, pinks, and white. Despite having their origins in Japan, these blooms thrive in most regions of the world. By altering the pH levels of the soil around the hydrangeas, you can change their color. Hydrangeas may be dyed any color, and all it takes is a little work to make your white hydrangeas appear their finest.
Check the pH of the hydrangea’s surrounding soil. The more acidic it is, the higher the level. Maintain a pH between 6.0 and 6.2.
- Large-leaved hydrangeas are stunning flowers with a wide range of hues, including vivid blues, purples, pinks, and white.
- Check the pH of the hydrangea’s surrounding soil.
Add a slow-releasing, evenly-balanced fertilizer with nitrogen, phosphorus, and potassium. Pick up some quality fertilizer from the supermarket, like 10-10-10.
Make sure the pH level is not too high by testing it once more. No more than 7.0 should be the pH level.
Once in late winter, fertilize the area around the hydrangea. Each 100 square feet of soil should receive 1 kg of fertilizer.
- Add a slow-releasing, evenly-balanced fertilizer with nitrogen, phosphorus, and potassium.
- Pick up some quality fertilizer from the supermarket, like 10-10-10.
Use a garden hose to water your plants on a regular basis, but watch out not to overwater them or let the water stand on the soil. The plant could wilt and decay if it receives too much water. To safeguard the plant, surround the base with 3 to 5 inches of mulch. Mulch around hydrangeas with compost or finely chopped wood bark.
White hydrangeas often contain no pigment and do not change color. White hydrangeas, however, have the potential to develop blue or pink tips as they age. By applying a balanced fertilizer that is low in phosphorus and maintains the acidity levels low, you can try to prevent it. If the pH levels in the soil need to be adjusted, you might need to fertilize in the spring or summer. Avoid trying to change the pH level too drastically at once because this could kill the plant by drying it out.
Make sure the hydrangea is in a location with cool afternoon shade and morning sun. Flowers may wilt and become brown if the weather is too hot and dry.
If you want to provide shade for a hydrangea, don’t put it under a tree because the tree will probably take the nutrients and hurt the hydrangea.
My hydrangeas won’t turn blue; why?
The acidity of the soil your hydrangeas are placed in affects the color of their flowers. So that’s it. There is no other cause. Don’t pass up the potted pink hydrangeas just because they aren’t blue, so if you go into Costco intending to buy yourself some pillow case-sized bags of potato chips, half a cow, 35 bottles of Windex, and a jar of pickles big enough to drive, don’t. That can be altered. Your pink hydrangeas can be changed to blue.
In general, you can change the acidity of the soil that pink hydrangeas are in to turn them blue, and if they’re in a container, it’s much simpler. The issue is that once the flowers have bloomed, you cannot modify their color. Before the flowers bud and bloom, you need to alter the soil’s acidity.
It’s not difficult, but you do need to purchase one unique ingredient. Love. I’m joking. If you’re not Rupert Murdoch, you can’t purchase love.
Aluminum sulfate, which sounds like something you’d only find in a lab, is what you actually need to buy, and you can get it right there in the gardening section of your neighborhood hardware shop or garden center. It’s cheap, completely harmless, and is actually used to cleanse water.
You still have time to adjust the flower color if your hydrangea bush looks like this. This is why if they become pink even though your hydrangea was blue when you got it.
Pink hydrangeas can be grown on soil with a pH higher than 6.0. Blue hydrangeas can be grown on soil with a pH lower than 6.0. Therefore, if you purchased a blue hydrangea in a container, it would no longer be able to grow blue after being planted in your soil. So how do you find out what your soil’s pH is? If you want to check the pH of your soil, you can get a little kit similar to a pool testing kit. It only takes a small amount of soil, some water, and pH testing powder in the container.
With a pH of between 7 and 7.5, the soil around my hydrangea plant is significantly off-target for a blue hydrangea. Therefore, that will result in a highly pink hydrangea. Which is good, but you should also try some new things. This summer, I want to try to grow blue hydrangeas, which calls for lowering the pH below 6.
I must add aluminum since it causes the pH of the soil to decrease. I just bought a container of Aluminum Sulfate because it seems like a hassle to crush cans and get them into powder form. The simplest approach to grow blue flowers is to mix this into the soil.
But in all honesty, you don’t need to check the acidity of your soil. Grab some aluminum sulphate (aluminum sulfate) and start stirring it into some water if your hydrangea blossoms are pink. If this is the case, you know that your soil’s acidity isn’t right for developing blue flowers.
Water the hydrangea while mixing 1 tablespoon of aluminum sulfate into 1 gallon (16 cups) of water. You’ll be closer to having blue hydrangeas than you were before if you start doing this once a month now, before your hydrangea’s flower buds begin to form.
I say, “you’ll be closer to having blue hydrangeas,” but I can’t promise it will because, despite what I’ve read on the matter, I’ve never actually attempted it. However, I have every reason to think it will succeed because I read about it online.
You can try doing this with other soil acidifiers like coffee grounds or pine needles, but chances are you won’t have enough grounds to sufficiently change the pH of your soil to produce a really brilliant blue unless you have an almost pathological addiction to coffee.
If your hydrangea is in a pot, it will almost certainly work because there is only a little amount of soil that needs to have its pH changed; however, hydrangeas in the garden are more difficult to manipulate. Additionally, a white hydrangea cannot ever be turned blue. Hydrangeas that are already pink or blue must be used for this. A white hydrangea’s only potential color change due to the acidity of the soil is a pink tint.
The technique I’m about to describe is intended to turn a pink hydrangea blue. Hopefully.
I’ve irrigated my hydrangeas with this mixture twice already, and I’ll continue doing so once every several months till I know if it was successful.
I don’t like posting things on my blog here unless I am absolutely certain that they work, but if they do, I’m cheating you out of an entire summer’s worth of blue hydrangeas. Don’t hold it against me if it doesn’t work for you now. I did warn you. I’m not to blame. I’m testing it out to see if it works, just as you are.
If it doesn’t work for you, simply get in your pickle jar automobile and go complain to the King of the Internet. He can frequently be seen in his front window. He’s frequently seen jumping around in flame-colored pants and using his nose to knock lamps off of tables.
