While baking soda can have some benefits for hydrangeas, the risks of overusing it are quite high. Here are a few key points about using baking soda on hydrangeas:
Potential Benefits Baking soda can help slightly adjust soil pH to be more acidic, which hydrangeas prefer
It may act as a protective barrier against some pests and diseases like powdery mildew.
Risks and Drawbacks Too much baking soda can cause more harm than good to hydrangeas. Baking soda does not provide the broad spectrum of essential nutrients that hydrangeas need to thrive and bloom
Excess sodium from baking soda can actually inhibit flowering and potentially damage roots.
There is no scientific evidence that baking soda boosts hydrangea flowering or growth.
Better Alternatives Use a balanced, slow-release fertilizer that provides all the necessary nutrients in the right proportions