One of the most valuable soil amendments and organic fertilizers is volcanic rock dust. Granite rock dust is one example, basalt rock dust is another.
Basalt is an igneous rock packed with trace elements. That’s why using this volcanic rock as a fertilizer provides your plants micro-nutrients that will nearly double yields. Minimum recommended application rate (for the first time) is: 3 tons/acre = 7.5 tons/ha or approximately 1 kg/1 sq.m.