The blue hydrangeas you had always desired were finally yours when you bought them, planted them, and the next year they flowered with enormously lovely…pink blossoms. Ugh! Why did that take place? What happened to your BLUE flowers? Can you change the color of hydrangeas to get them back? If you’re patient, yes…
The pH of the soil must be adjusted over a period of weeks, months, or even years in order to affect the color of your hydrangea bushes. Generally speaking, turning pink hydrangea blooms blue is harder than turning them pink. Therefore, you blue fans would need a little more perseverance and commitment. Check out our plant nursery’s enormous assortment of hydrangeas!
To find out where you stand, check your soil’s pH. For blue blooms, a pH of 4.5 to 5.5 is ideal. You might lose this battle if your pH is higher than 7.5. Because of the free calcium carbonate or marl that is common in soil with a pH this high, lowering the pH is particularly challenging.
Applying aluminum sulfate, elemental sulfur, or our Espoma organic soil acidifier can easily turn your hydrangea flowers blue. The chemical molecule aluminum sulfate lowers the pH of your soil. Pure sulfur, an ingredient that makes your soil acidic, is what is referred to as elemental sulfur. You remember the periodic table from science class in high school? Yeah, those elements. Both aluminum sulfate and elemental sulfur function by enabling your hydrangeas to access metal. The resultant reaction makes the soil more acidic, and your plant grows blue blossoms. Although aluminum sulfate works more quickly, elemental sulfur is the more affordable option. For this reason, most gardeners typically choose aluminum sulfate.
Apply 1lb (2 cups) of aluminum sulfate or 1/6lb (1/3c) of elemental sulfur around your hydrangea shrub for established plants. There may be variances in items and directions, so make sure to read the instructions on the box you purchase. In comparison to water dilution, a direct topdress to the soil around your hydrangea plant that covers the entire rootzone out to the dripline appears to be the most efficient and straightforward way. Late winter or early spring is the best time to administer the first dose.
Well-aerated sulfur is added. Don’t neglect this step because it’s essential to starting the chemical reactions. Any sulfur that got on your plant should be thoroughly rinsed off.
Check your soil’s pH once more in three months. The pH of your soil should hopefully be in the right range, but if not, repeat the treatment process until it is. You are on the right track and can simply administer another dose if you notice purple hydrangea flowers rather than pink ones.
What can you use to dye hydrangeas blue?
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.
Need hydrangeas sulfur to grow?
However, not all hydrangeas have blue flowers. Hydrangeas (Hydrangea macrophylla) are famous for their huge, ball-shaped clusters of blue blossoms. Because they are unable to absorb the metal necessary for the growth of blue flowers, plants growing in alkaline soil produce purple to pink flowers. Lowering the pH of the soil will produce bluer flowers because hydrangeas absorb more metal from acidic soil than they do from alkaline. To lower the pH of the soil around hydrangeas, a gardener can add sulfur in the spring. U.S. Department of Agriculture plant hardiness zones 6 through 9 are suitable for hydrangea growth.
Which fertilizer is ideal for blue hydrangeas?
When purchasing fertilizer, check the labels to see how much nitrogen (N), phosphate (P), and potassium are present (K). A general-purpose, balanced fertilizer such a 10-10-10 N-P-K or 12-4-8 N-P-K is typically best for hydrangeas. Consider using a fertilizer with additional phosphorus if you want your hydrangea blossoms to be bigger and more numerous.
Since phosphorus is the middle element, fertilizer with the formula 10-20-10 will do. Choose a slow-release granular fertilizer with the designation “bloom boost” if you’re looking into it because it might also include more phosphorus.
White vinegar: Does it turn hydrangeas blue?
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 can I get dark purple hydrangeas?
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.
Do hydrangeas turn blue from coffee grounds?
- Maintain low amounts of phosphorus, moderate levels of nitrogen, and high levels of potassium in the soil in order to make sepals bluer.
- Maintain high levels of nitrogen and moderate amounts of phosphorus while adding garden lime to the soil to give sepals a pinker hue.
- This should be completed in late autumn or early spring, well before flowering.
Can coffee grounds be used to change the color of hydrangeas?
Some gardeners claim that adding coffee grounds to the soil helped them successfully dye their hydrangeas blue. The soil becomes more acidic thanks to the coffee grounds, which makes it easier for the hydrangea to absorb metal. Fruit peels, grass clippings, peat moss, and pine needles are also believed to have a comparable impact.
Can eggshells be used to change the color of hydrangeas?
Crushed eggshells might be a good approach to grow pink hydrangeas. Eggshells will gradually degrade and lessen the acidity of your soil, which will make it more difficult for hydrangeas to absorb metal.
How do I make blue hydrangeas with vinegar?
To adjust the soil’s acidity and colour their hydrangeas blue, many gardeners add vinegar to their watering can. However, if you use Hydrangea Blue, a liquid fertilizer that yields blue flowers, you’ll probably get greater results.
How may sulfur be added to hydrangeas?
The pH of your soil can be lowered by adding elemental or granular sulfur if it is excessively alkaline. In many gardens in the Chicago region, plants like rhododendrons and azaleas might benefit from sulfur applications.
If your blue hydrangeas are starting to turn pink and you want to try to get the flowers back to blue, you should apply sulfur. In soils that are more alkaline, the blossoms turn pink. For every 100 square feet of planting space, add 3 pounds of sulfur annually. Applying twice, once in the spring and once in the fall, is ideal. Use half the suggested rate each time.
Incorporate water and sulfur into the soil. Sulfur works gradually. When applying, be careful to keep the dust out of your eyes and wear protective gloves.
- As your bulb displays bloom throughout the month, take pictures of them and note where to plant fresh bulbs in the fall to enhance the display. For a constant show from year to year, certain bulbs may eventually thin out and will need to be periodically replenished.
Make a plan to add bulbs that bloom at various times to your garden as you observe it during the spring and early summer to add more color. This will make ordering and planting bulbs later this year much simpler.
When they are in bloom, renegade bulbs that may have scattered themselves over the garden are simple to locate.
- Too many trees are buried underground. Find the trunk flare, or the point where the trunk spreads at ground level, to establish the appropriate planting depth for your new tree. Open the burlap to reveal the flare if the trunk flare is not visible. In order to expose the flare, you will need to put the tree higher in the hole and carefully remove the extra soil there.
In heavy clay soils, planting 2 to 3 inches above ground level is usually a good choice. It is advisable to avoid amending the backfill that goes back into the planting hole, but it is acceptable to do so in the soil immediately surrounding the tree. After the tree has been placed in the planting hole, it is recommended to remove the wire basket and burlap if the root ball seems to be loose.