1: The National Park Service recommends D/2 Biological Solution, a biological cleaner, that is safe from headstones. Other supplies should include a water spray bottle, plastic scrapers, soft brushes and even wooden skewers.

2. Thoroughly wet the headstone.

3. Gently scrape off any debris, dirt, loose rocks or moss that is on the surface. This can speed up the cleaning process.

4. Spray the compound, which is as safe as a kitchen or bathroom cleaner. It soaks into the stone to kill any growth over time.

5. Gently scrub to loosen dirt. Start with a large brush and then work up to toothbrushes or skewers to clean the cracks and fine details.

6. Rinse with water. Come back in a month or so to fully see the transformation because the compound embeds itself into the stone and breaks down any growth over time.