White residue on outdoor tables is a common issue caused by mineral deposits, hard water, or cleaning product buildup. To prevent this, regularly wipe your table with a mild soap solution and rinse thoroughly with distilled water to avoid mineral accumulation. For existing residue, mix equal parts vinegar and water, apply with a soft cloth, and scrub gently. Rinse well and dry to prevent streaks. Applying a protective sealant can also help shield your table from moisture and residue. Avoid harsh chemicals, as they may damage the surface. Consistent care will keep your outdoor table looking pristine for years.