"Unveiling the Truth: Can Aluminum Foil Transform Hydrangea Flowers into Stunning Blues?"
Originally Published 2 years ago — by House Digest
Contrary to online claims, burying aluminum foil near hydrangeas does not change their color. The color change is actually achieved by adding aluminum sulfate to the soil, which decreases the pH level and turns the flowers blue. However, not all hydrangea varieties can change color. To turn pink hydrangeas blue, mix 1 tablespoon of aluminum sulfate with 1 gallon of water and soak the base of the plant once a month for three months. It can take months or even up to a year for the color change to occur. To change them back to pink, use hydrated lime instead of aluminum sulfate.