Does rubbing a potato on windshield work for rain?

Using a potato to wipe the windshield does create a hydrophobic effect for a short time. This is because the starch in the potato forms a thin film on the glass surface, making it difficult for rainwater to adhere. The oil film is mainly formed by the accumulation of pollutants such as exhaust oil mist, dust, and tree sap. Relying solely on potatoes for long-term treatment may lead to repeated accumulation of the oil film, affecting driving visibility and safety. More effective solutions include using dish soap (which breaks down oil stains through lipophilic components), toothpaste containing abrasive particles (to gently remove surface dirt), or specialized oil film cleaners (with protective layer formulas). Sand particles on the glass surface should be removed first before cleaning to avoid scratches, and regular maintenance (such as wiping the windshield promptly after driving) can also delay the reformation of the oil film. Overall, potatoes are not a scientific or long-term solution. It is best to prioritize targeted cleaning products or professional services to ensure driving safety.