Is baking soda harmful to basil?
Certified GKH Gardening Expert
In VERY VERY small amounts, and used correctly as an insecticide and antifungal, it won't hurt them. If you add it to water into the soil as nutrients then it will have a devastating cascade of effects leading to the death of the plant. Baking soda has to be used correctly when it comes to gardening, as the sodium that it contains is way too much for most plants to be able to handle.