Herein, we report on the rapid and reproducible fabrication of Silver-Gum Arabic (Ag-GA) SERS substrates by electrochemical deposition. The fabrication method produces large area SERS substrate (40 µm x 20 µm) and requires less than 10 s, with 2 µL of a non-toxic solvent. This is a time-saving, environment friendly, high throughput and scalable method in comparison to the other ways of fabricating the SERS substrate. The fabricated samples are used for herbicide 2,4-D detection directly in aqueous solutions, with a detection limit down to 1 pM reported without the need for sample preparation.