Mustard stains on outdoor furniture cushions can be stubborn, but with the right approach, you can restore their freshness. Start by scraping off excess mustard with a dull knife or spoon. Mix a solution of warm water and mild dish soap, then gently blot the stain with a clean cloth. For tougher stains, apply a paste of baking soda and water, let it sit for 15 minutes, then rinse. Avoid harsh scrubbing to prevent fabric damage. For white or light-colored cushions, a diluted hydrogen peroxide solution (1:1 with water) can help lift the stain. Always test any cleaner on an inconspicuous area first. After treatment, rinse thoroughly and air-dry completely before using the cushions again. Regular maintenance and prompt stain treatment will keep your outdoor cushions looking their best.