How to Clean a Gravestone Safely (and When to Stop)

TLDR: If the headstone is stable and the surface isn’t flaking or powdery, you can usually do a light clean using clean water and a soft, natural-bristle brush. Wet the stone first, keep pressure low, and rinse often. Do not use bleach, vinegar, household cleaners, abrasives, or a pressure washer. If water and gentle brushing don’t shift the staining, or if the stone is cracked, crumbling, loose, or the inscription looks fragile, stop. That’s the point where it’s safer to check permissions and consider professional cleaning or restoration.

Cleaning a gravestone can be a genuinely meaningful thing to do, especially if you have not been able to visit for a while and the memorial is starting to look neglected. The problem is that stone does not behave like patio slabs or garden ornaments; once a surface has weathered, become porous or started to break down, the wrong cleaning method can remove material from the stone itself, not just the dirt on top.

This guide gives you a safe baseline approach, but it also draws a clear line around what you should not attempt. If you only take one idea from it, make it this: cleaning is an intervention, and the best results usually come from doing less, more gently, and stopping earlier than you think.

Do you actually need to clean it?

Before you reach for any product or brush, it’s worth asking what you are trying to achieve. Some memorials develop light weathering that is not harmful, and a headstone does not need to look “new” to look cared for. In conservation work, the aim is usually to remove what is actively damaging the surface, not to chase brightness for its own sake. That principle is reflected in Society for the Protection of Ancient Buildings (SPAB)’s guidance on caring for stone, which favours the mildest effective method over aggressive cleaning.

Practically, that means you should start by looking for signs of harm rather than signs of age. Heavy moss that traps moisture, green algae films, thick lichen growth over inscriptions, and black pollution staining that is clearly building up are more likely to justify intervention. A light patina, faint discolouration, or minor darkening can often be left alone, especially if the stone is older or softer.

Safety check first: stone type and condition

Before you clean anything, treat it like a quick condition check rather than a cleaning job. Walk up close, look at the face of the stone, then look at the edges, the base, and the joints. You’re checking for signs the memorial is already breaking down because cleaning a failing surface tends to accelerate the failure.

If you can rub the surface lightly with a fingertip and it leaves powder on your skin, or if the stone is flaking, cracked, hollow-sounding, or visibly delaminating, stop there. Cleaning a memorial that is already chipped, loose, or crumbling can turn “a bit tired” into “permanently damaged” in one afternoon. Using the gentlest method first is always worth it.

There’s also a safety angle: a memorial that has movement at the base, or looks like it may rock when touched, is not a DIY problem. The UK guidance on burial ground memorial safety is aimed at operators, but the principle applies to families too: unstable memorials need a sensible, proportionate response, not hands-on testing.

If the stone looks sound, inscriptions are not crumbling, and nothing appears loose, you can move on. If you’re unsure, you’re already in “stop” territory.

Stone type matters more than effort

Most DIY damage comes from treating every gravestone as if it’s the same material. It isn’t. Granite is generally harder and more resilient. Slate is often durable too, though it can split along layers. Marble and limestone are softer and more porous, which means they stain more easily and can lose surface detail if you scrub. Sandstone varies wildly depending on its composition, but it is often the least forgiving.

This is why the best advice looks boring: water, soft brush, light pressure. The moment you introduce chemicals, scraping, or repeated scrubbing, the risk climbs, especially on older stones where the surface has already weathered.

If you want a useful mental model, think “surface integrity”. A stone can look intact from a distance while the outer layer is actually weakened. Your job is not to win a fight with the stain. Your job is to avoid removing stone.

The safest DIY clean: the baseline most people should stick to

If the memorial is stable and the surface is in decent condition, keep the method intentionally minimal.

Start by thoroughly wetting the stone with clean water. This matters more than people think because it reduces friction and stops grit being dragged over a dry surface. Use a soft, natural-bristle brush or a soft cloth, then work gently over the face of the stone with light, even strokes. You can clean from the bottom upward to reduce streaking, but the bigger point is to keep pressure low and rinse often so loosened dirt is washed away rather than scrubbed back in.

If you’re cleaning around lettering, slow down. Inscriptions are where detail is easiest to lose, and it’s also where people tend to focus their scrubbing. A gentle pass, then rinse, then reassess is safer than “one more go”.

If water and gentle brushing makes no meaningful difference, that is your signal to stop. Pushing beyond that is where damage tends to happen.

What cleaner should you use on a gravestone?

Heritage-focused organisations land in the same place, but with the reasoning spelled out. Guidance repeatedly returns to least abrasive methods, warning against high pressure water jets, abrasives, and chemical products in most circumstances. Their stone cleaning advice is a good reference for “do less, but do it safely". If you are determined to use a specialist product, you want something formulated for memorial stone, such as GraveClean’s Headstone Cleaning Solution.

What not to use and why it causes damage

This is one of the few places where a short list helps, because the “don't use” items are discrete and common.

Avoid:

• Bleach, patio cleaners, acidic or alkaline products, ammonia solutions
• Vinegar or other home “hacks”
• Wire brushes, scouring pads, abrasive sponges
• Pressure washers or jet washes
• Paint, sealants, or “stone brighteners” you do not fully understand

The key problem is not only immediate damage. It’s what gets left behind. Historic Environment Scotland explicitly warns that household bleaches and similar products can deposit salts and drive further decay, and it recommends professional advice.

If you’ve ever seen a memorial that looks clean for a few weeks and then turns patchy or develops strange brown staining, it’s often residue, not “new dirt”.

If it doesn’t lift, don’t fight it

This is where most people go wrong, even when they started carefully.

A gravestone can look “stained” for different reasons. Some of it is surface dirt and biological growth that responds to gentle cleaning. Some of it is embedded pollution, mineral staining, or long-term weathering. The difference matters because embedded discolouration does not respond to effort. It responds to methods, and some of those methods are not appropriate for DIY.

If you’re cleaning gently and the result isn’t changing, avoid the urge to scrub harder. Instead, reassess what you’re dealing with and switch to a more appropriate memorial product rather than escalating your force. For example, if you’re seeing stubborn black spotting that looks like it’s “in” the stone rather than sitting on top, GraveClean’s Black Spot Remover for Headstones is designed for that specific problem, whereas brute-force scrubbing is more likely to roughen the surface and make future staining worse.

When to stop and call a professional

You should stop DIY cleaning if any of the following are true:

• The stone is flaking, powdery, cracked, or visibly eroding
• The memorial is loose, rocking, or the base looks unstable
• The inscription is shallow, fragile, or already losing definition
• The staining is heavy and not shifting with water and gentle brushing
• You are unsure about the stone type, the cemetery’s rules, or what’s permitted

If you want to understand what “professional” means in practice, GraveClean explains the approach and constraints in plain terms on our cleaning process for memorials and headstones.

And if you already know you’re beyond DIY, the most direct option is the headstone cleaning and restoration service, which is designed for exactly the situations described above.

Permissions and rules: the part people skip until it’s a problem

Even if your cleaning method is gentle, the cemetery may have rules about what can and cannot be done. Some allow light cleaning. Others require permission for anything beyond basic tidying, particularly in churchyards, older cemeteries, or where memorials have heritage sensitivity.

If you’re unsure, the safe approach is to pause and check. It’s always easier to ask first than to undo work later.

What a professional does differently

A professional will start by assessing the stone’s condition, stability, and vulnerability, then choose the mildest method that achieves a safe improvement. In practice, that means controlled cleaning, stone-appropriate treatments, and restraint around inscriptions and damaged areas. It also means knowing when cleaning is the wrong intervention and when a different form of restoration is needed.

That approach is consistent with conservation guidance more broadly, including Historic England’s preference for minimal intervention and least aggressive methods when dealing with stonework. It’s also consistent with the War Memorials Trust stance that cleaning should only be carried out when deposits are disfiguring, damaging, or obscuring inscriptions, and that over-cleaning can shorten a memorial’s life.

Final thoughts

If you keep your DIY approach conservative, you can often make a memorial look cared for without taking risks. Wet the stone first, use clean water, a soft brush, and a light touch, then stop early if the result is not changing.

The moment you start reaching for stronger products, heavier scrubbing, scraping, or pressure washing, you are more likely to damage the memorial than to improve it. If the stone is fragile, heavily stained, unstable, or you are uncertain about permissions, professional help is the safer option.

For anything that feels beyond a gentle clean, start with GraveClean’s headstone cleaning and restoration service, or read how our cleaning process works so you know what to expect.

FAQs

Can you clean a gravestone yourself?

Sometimes, yes, but only if the memorial is stable and the surface is in reasonable condition. A gentle clean with water and a soft brush can remove loose dirt and light biological film without harming the stone. Where people get into trouble is assuming “more effort” equals “more result”. If the stone is flaking, cracked, powdery, or the inscription is already fragile, DIY cleaning is more likely to remove stone than remove dirt, so it’s safer to stop and get professional advice.

Should I use bleach on a headstone?

No. Bleach can weaken stone surfaces, leave residues, and cause long-term discolouration, especially on softer and more porous stones. If a product is designed to strip, brighten, or disinfect household surfaces, it does not belong on a memorial.

What cleaner is safe for a gravestone?

For most people, the safest answer is clean water and a soft brush, used gently. If the stone is sound and you need something beyond water, use a cleaner made specifically for memorial stone. GraveClean’s Headstone Cleaning Solution is a sensible step up from water because it’s aimed at the kind of organic film and general grime you actually see on headstones.

When should I call a professional headstone cleaner?

Call a professional if DIY cleaning does not improve the stone, if staining is heavy or embedded, if the memorial is old or fragile, if the inscription is fading, or if the headstone is unstable. If you want to see what professional care involves before committing, GraveClean explains its memorial cleaning process clearly, and the cleaning and restoration service is the right route when preservation is the priority.