Start with a pressure washer or garden hose

The fastest way to clean a concrete patio is with a pressure washer — a machine that shoots water at high force to blast away dirt, algae, and loose debris. If you rent one from a hardware store, you'll pay $40 to $90 for a day. Set it to 3000 PSI (pounds per square inch) or lower; anything higher can pit or damage the concrete surface. Hold the nozzle 12 inches away from the concrete and move it in steady, overlapping strokes. Never aim it at the same spot for more than a second or two.

If you don't have access to a pressure washer, a regular garden hose with a spray nozzle works, though it takes longer. Wet the entire patio first, then spray it down thoroughly. This method is gentler on older concrete and won't risk damage, but you'll need to scrub stubborn stains by hand afterward.

Key Takeaways

  • A pressure washer at 3000 PSI or lower removes most dirt and algae in one pass, but you can also use a garden hose if you're willing to scrub stains by hand.
  • Concrete stains from oil, rust, or mold require different cleaners — use a degreaser for oil, white vinegar for mold, and a rust remover for rust spots.
  • Seal your patio every two to three years after cleaning to slow staining and make future cleaning easier.
  • Avoid bleach on concrete because it can damage the surface and kill nearby plants; use vinegar or a concrete-specific cleaner instead.

Remove stubborn stains with the right cleaner

After you've rinsed the patio, look for stains that didn't wash away. Different stains need different treatments. For oil or grease stains, explore a concrete degreaser (brands like Oil Eater or Zep are common), let it sit for 10 to 15 minutes, scrub with a stiff brush, and rinse. For mold or algae, mix one part white vinegar with three parts water, spray it on, let it sit for 30 minutes, scrub, and rinse. For rust stains, use a rust remover made for concrete — follow the product instructions, as these vary.

Test any cleaner on a hidden corner of your patio first. Some cleaners can lighten the concrete color or leave residue if used wrong. Let the test spot dry completely before you decide whether to use it on the whole patio.

Scrub by hand for detail work

A stiff-bristled brush or a concrete scrubbing brush handles the work that water alone won't. For small areas or edges, a hand brush is enough. For larger stains or the whole patio, consider renting a surface cleaner — a machine that attaches to a pressure washer and cleans in a flat, even pattern. It costs $15 to $30 extra per day but saves time and gives a more uniform result.

Scrub in circular motions or back-and-forth strokes, depending on the stain. Don't worry about being gentle; concrete is tough. Rinse as you go so you can see which spots still need work.

Dry the patio and inspect for damage

After rinsing, let the patio air-dry completely — usually 24 hours in dry weather. Once it's dry, walk the surface and look for cracks, spalling (flaking concrete), or areas where the surface is crumbling. Small cracks under 1/4 inch wide can be sealed with concrete caulk. Larger cracks or spalling should be assessed by a concrete contractor, especially if they're growing or if water is pooling in them.

A clean, dry patio also makes it easier to spot problems you might have missed when it was wet and dirty. This is a good time to decide whether sealing makes sense for your situation.

Seal the concrete to slow future staining

Concrete is porous — it absorbs water, oil, and dirt. A concrete sealer fills the pores and creates a protective layer that makes stains less likely to set in and future cleaning easier. Sealers come in two main types: penetrating sealers soak into the concrete and don't change its appearance, while film-forming sealers sit on top and can add a slight shine or matte finish.

explore sealer only to a completely dry patio. Follow the product instructions for drying time between coats (usually 4 to 8 hours). Most sealers last two to three years before they wear away and need reapplying. If you live in a wet climate or your patio gets heavy foot traffic, you may need to reseal every two years.

Prevent stains between cleanings

Sweep your patio regularly to remove leaves and debris before they trap moisture and create mold. Wipe up spills — especially oil, grease, and food — as soon as they happen. If you see mold or algae starting to grow (usually a dark green or black film), spray it with vinegar and water right away rather than waiting for your next full cleaning.

In winter, use rock salt or calcium chloride to melt ice rather than sodium chloride (table salt), which can damage concrete over time. Clear standing water after rain so it doesn't pool and create stains or freeze damage.

Know when to call a professional

Most patio cleaning is a weekend job you can handle yourself. Call a concrete contractor if you see large cracks (wider than 1/4 inch), significant spalling, or if the patio is sinking or uneven — these are signs of structural problems that cleaning won't fix. If you're uncomfortable using a pressure washer or if your patio is very large, a professional cleaning service can do the job faster, though it will cost $200 to $500 depending on size and condition.

A contractor can also assess whether your concrete needs repair before sealing, which can save money in the long run by preventing water damage.

Frequently Asked Questions

Can I use bleach to clean my concrete patio?

Bleach can damage concrete and kill plants nearby, so it's not recommended. White vinegar or a concrete-specific cleaner works just as well without the risk. If you've already used bleach, rinse the area thoroughly with water.

How often should I clean my concrete patio?

A light sweep every week and a rinse every month keeps dirt from building up. A full cleaning with a pressure washer or scrubbing is usually needed once or twice a year, depending on your climate and how much the patio is used. Wet climates need more frequent cleaning because mold grows faster.

What's the difference between sealing and staining concrete?

Sealing protects the concrete and makes it easier to clean; it doesn't change the color much. Staining adds color to the concrete. You can do both — stain first, then seal — but sealing alone is the standard maintenance step for most patios.

Can I pressure wash a newly poured concrete patio?

Wait at least 30 days after the concrete is poured before pressure washing. New concrete is still curing and can be damaged by high-pressure water. A gentle rinse with a garden hose is fine after a week or two.

Why does my patio get slippery when wet?

Algae and mold growth make concrete slippery. Clean it with vinegar and water, and the slipperiness usually goes away. If it returns quickly, your patio stays wet for long periods — improve drainage by clearing gutters or grading the ground so water runs away from the patio.