Hydrangeas are beautiful flowers. They accentuate the landscape of any home very well. Their full bunches of flowers and elegant colors are sure to catch anyone’s eye. They are unique because most of these gorgeous flowers can change colors. This gives us the opportunity to try and pick the color of our hydrangea blooms that we have planted in our yard.
About Hydrangeas
There are approximately 20 different types of Hydrangeas. Many of which have their own specific colors (usually beige, white, yellow, pink or blue). Each type may have different colors within their subcategory but, they will each only bloom with one color flower. However, the Hydrangea Macrophylla (lacecap, mopheads and bigleaf) can change the color of their flowers.
How can they do that?
It is because these amazing flowers get their colors solely from the pH levels in the soil they are growing in. This means they can bloom pink, then blue, and then back to pink.
How Can I get Blue Hydrangeas in my Yard?
Some of them naturally bloom in blues just be sure to check the tag. If you want to make sure you get blue there are a few things you can do.
Where to Start
Start by testing the pH of your soil. This can be done by purchasing a soil test kit. The pH scale goes from zero to 14 with seven being neutral. Anything lower than 7 is considered degrees of acidity in the soil. Anything higher than 7 is considered degrees of alkalinity.
Now What?
Once you know the pH of your soil, you will know what color to expect. Since we are going after blue flowers, you need your soil’s pH level to be at 5.5 or lower. For pink flowers, the plants need neutral to alkaline soils (pH 6.5 and higher). For purple color (or a mix of blue and pink flowers on the same plant), the pH of the soil must be 5.5 and pH 6.5
Umm, My Soil’s pH is too high
Don’t worry! You can easily fix this so that you can still achieve those gorgeous blue blooms you are looking forward to. All you have to do is pick up some of the soil add ins and put it in the soil when you plant your Hydrangeas.
Go Slow
When you are altering the pH level of your soil, remember that it works best if you can do is slowly as rapid alterations can wreak havoc on your plants.
How Do I Keep Them Blue?
If your soil’s pH is naturally in the right zone to make blue flowers there isn’t much more you need to do. If you had to alter the pH level of your soil, you will need to keep mixing the acidifier into the top layer of soil near the roots of your plant.
My Flowers are Light Blue and I was Hoping for Brighter Blue
I honestly think this is the coolest part of this Hydrangea plant. If your blooms are not as vibrant as you were hoping for, simply add more of the soil acidifier(or add in) to your soil and your blooms should become brighter. Just be sure to remember that it may take upwards of a month or more for the color change to take place. If you are unsure if you should add more, you can also check the pH level in the soil again.
Taking the More Natural Route
If adding a soil acidifier to your soil isn’t something that you would like to do but, still want those beautiful blue blooms than you need to use natural acidifiers. That typically means using something like pine needle mulch or, pine needle bark. Both of these will help naturally add acid to your soil.
Other Tips
Before you begin changing things around with your soil’s pH, check and make sure that the other plants near your hydrangeas also like acidic soil.
Also keep in mind that if your hydrangea plant is near concrete, it may be more difficult to turn your hydrangea blue. Most concrete contains lime which tends to give off lime. Lime is a common additive if you are trying to turn your blooms pink thus, making it difficult to turn your blooms blue.
If your soil is naturally more alkaline based, it will be harder to get the blue blooms you are looking for. The alkaline holds the aluminum (which it needs to turn blue) captive so it is unavailable for the plant. Adding a high-phosphorus fertilizer can help release that aluminum for the plant.
Growing your hydrangeas in a container will give you much better control of the pH balance of the soil resulting in a better chance in getting the exact color you want.
Bonus Tip
Test the pH level of your water. If it is above 5.6 you may struggle with getting the blue you have been looking for.
No matter what color your Hydrangeas are, they are sure to be beautiful. Be patient with them as it takes trial and error to get things ‘just right’. The beauty of hydrangeas is: they will continue to change as your soil changes. If you don’t have the right shade this year, try again next year.