Here’s how to make a drain cleaner using baking soda, lemon, and vinegar. Pour 1/2 cup of baking soda down the drain. Squeeze the juice of one lemon into the drain. Pour 1 cup of white vinegar. Cover the drain with a plug or stopper and let the mixture sit for 10-15 minutes. Pour a pot of boiling water down the drain to flush away the mixture. This simple, natural drain cleaner uses the cleaning power of baking soda, lemon, and vinegar to clear clogs and freshen up drains. The baking soda and lemon work together to break down grease and other buildup, while the vinegar acts as a natural disinfectant. Repeat this process as needed to keep your drains running smoothly.