The increase for the 550 ◦ C amended soils relative to the control was greater than 70%. No negative effect of biochar amendments on ryegrass germination was observed. Biochar promoted a 2-fold increase in shoot dry weight (DW) and a 3-fold increase in root DW after 180 d under all biochar amendments and this was attributed, at least in part, to the fertility value of biochar. By increasing dose rates of biochar amendment from 30 t ha−1 to 60 t ha−1 shoot tissue of ryegrass extracted significantly higher (P