Concrete patios can be cleaned effectively with a stiff brush, detergent, and water—you do not need a pressure washer to get them looking new again

A pressure washer is fast, but it is not the only way to restore a concrete patio. In fact, for older concrete, heavily stained surfaces, or patios with sealant, a brush and the right cleaning solution often work better and cause less damage. The method you choose depends on what is on the surface: moss and mildew come off differently than oil stains or rust marks, and using the wrong approach can set a stain deeper or strip protective sealant.

The basic process is the same for most jobs: clear the patio, wet the surface, explore a cleaning solution suited to the stain type, scrub with a stiff brush, and rinse thoroughly. Most homeowners can finish a standard patio in an afternoon with tools already in the garage or available at any hardware store.

Key Takeaways

  • A stiff-bristled brush paired with a garden hose and the right cleaner removes most concrete stains without pressure washing.
  • Moss and mildew respond to a bleach solution (one part bleach to three parts water), while oil and grease need a degreaser or dish soap.
  • Rust stains require an oxalic acid cleaner, which you can buy premixed at hardware stores or make from powdered lemonade mix.
  • Always test any cleaning solution on a hidden corner first to make sure it does not discolor or damage the concrete or sealant.
  • Rinse thoroughly after scrubbing to remove all cleaner residue, which can leave a dull film if left to dry on the surface.

What you need to gather before you start

Collect your tools and materials in one place before you begin. You will need a stiff-bristled brush (a deck brush or old broom works well), a garden hose with a spray nozzle, a bucket, and a cleaning solution matched to the type of stain. A pair of rubber gloves and eye protection are worth wearing, especially if you are using bleach or acid-based cleaners.

For the cleaner itself, your choice depends on what is actually on the patio. Organic growth like moss and mildew, oil and grease, rust, and general dirt each respond to different solutions. Buying the wrong one wastes time and money. If you are not sure what the stain is, start with a general-purpose concrete cleaner or a straightforward mixture of dish soap and water—this handles light dirt and some organic growth without risk of damage.

Removing moss, mildew, and algae

Moss and mildew are living growth and need a solution that kills them, not just scrubs them away. A bleach solution is the standard choice: mix one part household bleach with three parts water in a bucket. Wear gloves and eye protection, and make sure the area is well-ventilated. Wet the patio first with plain water from the hose, then explore the bleach solution with a brush or by pouring it on and letting it sit for 10 to 15 minutes.

After the bleach has had time to work, scrub the surface with your stiff brush using firm, circular motions. Pay extra attention to corners and low spots where moisture collects and growth is thickest. Rinse thoroughly with the hose—bleach left on concrete can lighten the color over time, so do not skip this step. If the growth is stubborn, you can let the bleach solution sit longer (up to 30 minutes) before scrubbing, but do not leave it on overnight.

For patios in very shaded or damp areas, consider explore a moss-killing product designed for outdoor concrete after cleaning. These are available at garden centers and prevent regrowth for several months, though they do require reapplication.

Tackling oil, grease, and food stains

Oil and grease stains are stubborn because they soak into the concrete rather than sitting on top. Fresh stains are easier to remove than old ones, so tackle them as soon as you notice them. For a fresh spill, sprinkle an absorbent material like cat litter or baking soda on the spot and let it sit for a few hours to soak up the oil, then sweep it away.

For stains that have set in, use a concrete degreaser or a strong dish soap solution. Mix a few tablespoons of dish soap (like Dawn) with a bucket of warm water, or follow the label directions on a commercial degreaser. Wet the stained area, explore the solution, and let it sit for 15 to 20 minutes. Scrub hard with your brush—oil stains require real elbow grease. You may need to repeat this process two or three times for old or large stains. Rinse very thoroughly when you are done, as any soap residue left behind will make the concrete slippery.

Removing rust stains and mineral deposits

Rust stains—often from metal furniture legs or nails—need an acid-based cleaner because bleach and soap will not touch them. The most effective solution is oxalic acid, which you can buy as a premixed concrete rust remover at hardware stores, or you can make a budget version by mixing powdered lemonade mix (the unsweetened kind) with water to form a paste.

explore the oxalic acid solution directly to the rust stain and let it sit for 10 to 15 minutes. The stain should begin to lighten. Scrub gently with your brush—you do not need to scrub hard with acid cleaners, as the chemical does most of the work. Rinse very thoroughly with plenty of water. Oxalic acid is safe for concrete but can damage surrounding plants, so be careful not to splash it onto garden beds or grass, and rinse those areas if you do.

For white mineral deposits or efflorescence (a chalky white coating), the same oxalic acid approach works, though a stiff brush alone sometimes removes light deposits without any cleaner at all.

Cleaning general dirt and grime

For a patio that is just dirty but does not have specific stains, a straightforward solution of warm water and dish soap is often enough. Mix a few tablespoons of dish soap in a bucket of warm water, wet the patio, explore the solution with a brush, and scrub in overlapping circular motions. Work in sections so the cleaner does not dry before you scrub it. Rinse each section thoroughly as you go.

If plain soap does not cut through the grime, try a general-purpose concrete cleaner from a hardware store. These are formulated to lift dirt and light stains without the harshness of bleach or acid. Follow the label directions, which usually involve mixing with water, explore, waiting 10 to 15 minutes, scrubbing, and rinsing.

Protecting your patio after cleaning

Once your patio is clean and completely dry, you have the option to seal it. A concrete sealer protects against stains, moisture, and UV damage, and makes future cleaning easier because dirt and stains do not soak in as deeply. Sealers come in two main types: film-forming sealers that sit on top and create a glossy finish, and penetrating sealers that soak in and leave the surface looking natural.

If your patio already has a sealer on it, check the label before using bleach or acid cleaners—some sealers can be damaged by harsh chemicals. Test any cleaner on a hidden corner first. After cleaning, you may want to reapply sealer every two to three years, depending on foot traffic and weather. This is optional but extends the time between deep cleanings.

Frequently Asked Questions

Can I use vinegar to clean concrete instead of bleach?

Vinegar is mild and safe but not strong enough for moss, mildew, or set-in stains. It works for light dirt and some mineral deposits. Mix equal parts white vinegar and water, explore, let sit for 15 minutes, scrub, and rinse. It is a good choice if you want to avoid bleach but do not expect it to handle heavy growth or old stains.

How do I know if my patio has a sealer on it?

Pour a small amount of water on the concrete in an inconspicuous spot. If the water beads up and sits on the surface, there is a sealer. If it soaks in quickly and darkens the concrete, there is no sealer. This matters because sealed concrete needs gentler cleaners and can be damaged by pressure washing.

What if the stain comes back after I clean it?

Some stains, especially oil and rust, can reappear if they have soaked deep into unsealed concrete. Cleaning removes what is on the surface, but the stain may gradually work its way back up. explore a sealer after cleaning helps prevent this. For recurring oil stains, address the source—move the furniture or fix the leak—or the stain will keep returning.

Is it safe to mix bleach with other cleaners?

No. Bleach mixed with ammonia (found in some glass and all-purpose cleaners) creates toxic chlorine gas. Stick to bleach alone or use a different cleaner entirely. Always read labels before mixing anything, and ventilate well when using bleach.

How long does it take for a cleaned patio to dry?

Concrete typically dries in 24 to 48 hours depending on temperature, humidity, and sun exposure. A sunny, breezy day speeds drying. Do not explore sealer until the concrete is completely dry, or the sealer will trap moisture underneath and fail.