If you are considering purchasing light-colored flagstone for a walkway, there is a major maintenance factor you need to consider before making your final decision. Whether you opt for a man-made product or natural stone pulled right from the earth, light colors are highly susceptible to unsightly staining over time.
Spotting the Issue: Dirt or Mold? Eventually, you may notice the surface of your stone becoming completely covered in dark patches. While some of this might be surface dirt splashed up during a heavy rainstorm, which can easily be hosed off other stains are far more stubborn. Dark mold frequently takes hold on these porous surfaces. When a walkway starts looking persistently dirty and a standard hose won't clear it, you are likely dealing with a deeper mold or mildew issue rather than just topsoil.
Comparing Materials One of the best ways to diagnose the severity of your flagstone problem is to look at the surrounding areas. If the adjacent concrete sidewalk or a nearby planter is completely clean and lacks that same dark mold, it tells you the issue is specific to the flagstone material itself. Seeing this stark variation between standard concrete and your man-made or natural flagstone indicates that the stone is particularly susceptible to whatever organic growth is happening in your yard.
How to Safely Clean Your Walkway
If you decide to tackle the grime, you must proceed with caution to avoid ruining an expensive walkway:
Test first: If you are going to buy a chemical cleaner, always test it on a small, inconspicuous area before applying it to the entire surface.
Contact the manufacturer: Reach out to the manufacturer to get their specific product recommendations for cleaning.
Get it in writing: Do not just trust a representative who blurts out a product name over the phone. Find their official website or request an email so you have their approved cleaning methods in writing.
Ultimately, if the flagstone requires constant, aggressive maintenance just to look presentable, you might eventually find yourself considering a full replacement. Do your research upfront to ensure you know what kind of upkeep your new walkway will demand.
Three Key Tips for Flagstone Maintenance
Always do a patch test: Never apply a new chemical cleaner to your entire walkway without testing it on a small, hidden section first to ensure it doesn't discolor or damage the stone.
Demand written guidelines: When contacting a stone manufacturer for cleaning advice, get their recommendations in writing to protect yourself and your investment if a recommended product ends up causing damage.
Use the surrounding environment as a control: Compare your flagstone to adjacent concrete or planters to determine if the mold or dirt issue is isolated strictly to the stone's surface or if it's a wider environmental issue.
