It wouldn’t happen overnight, of course, but it wouldn’t take much more effort than you put in when you were in the fourth grade working on your science fair project, would you be interested?
The following is a guide on how to alter the color of hydrangeas from pink to blue.
Changing Hydrangeas from Pink to Blue
What alters the color of hydrangeas?
The color of hydrangeas, with the exception of white varieties, is determined by the pH level of the soil in which they are grown. The alkalinity of the soil determines the shade of pink that the blossoms will be.
Increasing the acidity of the soil is the best way to transform pink hydrangeas into blue ones (or to prevent blue hydrangeas from turning pink).
So, you’ll need to increase the acidity of your soil if you want your hydrangeas to develop the stunning, iridescent violet-blue hue that these plants are famous for having.
Because of this, the aluminum in the soil is able to be released to your flowers, which assists in giving them a bluish colour.
Check the pH of your soil
A very little sample of soil is all that is required to determine the pH level.
If you know what “pH level” refers to, you get extra credit; I searched it up, and I discovered that “pH” stands for “potential of hydrogen,” which, translated into layman’s words, refers to the concentration of hydrogen ions in soil.
The alkalinity of your soil will increase proportionately with the concentration.
Check the pH of your soil first to see how difficult or simple it will be to bring it down to the desired level; for blue blooms, you should aim for a pH of between 5.2 and 5.5.
How to alter the pH of the soil for hydrangeas?
Even while there are certain solutions on the market that can bring the pH down, the most effective method is always one that occurs naturally, even if it does take a little bit more time.
If you use organic mulch, it will assist to acidify the soil, and it will also be highly useful for the microbial life in your soil, as well as improve the quality of your soil.
You may try one that is made out of pine needles, pine bark, sawdust, citrus peels, vegetable peels, or even coffee grounds. In addition to that, it’s an effective approach to get rid of waste from the kitchen.
Moreover, eggshells that have been crushed will make the soil more acidic. Combine them with citrus peel and coffee grinds, then incorporate them into the soil.
Reduce Soil pH with Coffee Grounds
When should you perform this? After the bowl is filled, carry it outside to feed the hydrangeas. Keep the peels and grounds in a small bowl on the countertop.
Your hydrangeas should become significantly more blue by next year as the acidity of the soil gradually rises.
Reduce Soil pH with Aluminum Sulfate
Adding sulfuric acid, aluminum sulfate, or elemental sulfur to the soil is the most efficient technique to lower the pH of the soil.
There are items available to assist you in accomplishing this task.
Aluminum will be added to the soil as a byproduct of the decomposition of the organic molecules (making it more acidic).
You may find one from some other Garden Rich Aluminum Sulfate at Amazon.
What to do if hydrangeas turn too blue?
If this is the case, you can make your soil more alkaline by adding Garden Lime. Gardener’s Supply sells a bag of 6.75 pounds of Garden Lime for $8.99.
You may find one on Amazon.