go to local garden center and ask for hydrated lime
texas grass Reviewed by texas grass on . noob ph question hey guys, gotta question here.. so if I wanted to raise ph levels of my soil.. could i use some ph/alkalinity up for spas. The ingredient is "sodium hydrogen carbonate" Could i just mix this into my water in very small amounts to make the soil less acidic.. i think another name they use for it is "soda ash" Rating: 5