also found this at bottom of this page
Down To Earth Distributors - natural products for the home and garden


To raise the pH add oyster shell lime or liquid calcium. To lower the pH use Sul-Po-Mag (K-Mag) or powdered sulphur. An abundance of organic matter in the soil will help plants accept a wider range of pH.


or use a good liquid like general hydroponics
ph up This Base solution is formulated using Potassium Hydroxide and Potassium Carbonate
ph down Phosphoric acid