Pre-treatment for DIY patio cleaning. It is advisable to treat your driveway before pressure washing it help remove the most stubborn weeds, oil, or organics.

This quick blog will outline how to pre-treat the 3 most common marks on your patio or driveway. That is weeds, oil stains, and organic growth such as lichen and algae.

The weeds can grow very high with very long roots which become harder to remover over time. Weeds, oil and organic growth on your patio, can become particularly stubborn from which a home use pressure will not remove the stains. Therefore, we recommend that you pre-treat these stains with something you may have in your cupboard at home. This will allow the product to penetrate and uplift the marks, increasing the chances of complete removal of the stain. If the issue persists you may have to try multiple applications and pressure washing. Heavy oil or organic growth combined with years without treatment allow the marks to penetrate deep into the hard surface on your patio. How deep they penetrate depend on the type of hard surface.

This blog is intended for DIY use. Professionals please contact Surrey Jet Washing for further support on removing the most stubborn marks.  

Pre-treatment of weeds

If your driveway, patio, or other hard surface has stubborn weeds consider a pre-treatment prior to pressure washing. You can visit your local hardware store and pick-up some weed killer, although, although, some professional grade weed killers require a license to use (source). The downside of these is that they can become costly, dangerous and ineffective.  

Large Weeds on Block Paving

Another option is to use a high concentration of salt water. Salt is natural, readily available and effective when used correctly. Do not to use the salt near grass or flower beds as it reduces the quality of the soil for further growth. To create a natural salt recipe for weeds; mix equal mixture of salt to water to a squirt bottle, then add a splash of vinegar and washing up liquid. This lowers the surface tension of the water allowing the weeds to absorb the salt mixture.

Before applying the saltwater mixture, water nearby plants, grass until they are fully saturated. To reduce the damage to nearby flowers and grass, apply the saltwater mixture carefully to the weeds; the salt will then leach below to the roots of the weeds. Once fully applied, re-water nearby grass, plants and other vegetation until fully saturated this limits the amount of damage that may occur. Apply the mixture a day or two before pressure washing. Then before pressure washing pull the weeds out fully including the roots. This limits the amount of long term weed regrowth. Once clear, pressure wash as usual.

In sum, the pre-treatment to cleaning your patio with weeds use a weed killer from your local hardware store and use as advised on the bottle, or use a saltwater mixture. Be aware some professional weed killer needs licencing, whilst saltwater solution can be made with household products.

Pre-treatment of oil stains

Oils are a variant of grease, therefore, the product to help break down these oils should be a type of degreaser. Once you first notice an oil stain, apply a dish soap and scrub to allow the soap to penetrate the grease through the hard surface. The type of material to scrub with depends on the type of hard surface to avoid any damage or scratches. Once the dish soap has been sufficiently applied, generously pour traffic film remover (TFR) which can be found at your local car parts shop, more. a heavy duty degreaser from the hardware shop can also do the same job. This helps disperse the oil from penetrating nearby patio or driveway pavers.

Oil on Pavers

Leave the dish soap and degreaser to soak into the patio or driveway for an hour. Then you can jet wash the stain. If the stain persists, try a few treatments. If the stain is still there, call a professional such as Surrey Jet Washing. As there are other specialists treatments including burning it off or use hot water to remove the stain.

If cleaning your patio use a pre-treatment to remove oil stains apply dish soap and let it dwell. A heavy duty degreaser applied over the top will also help. Try numerous treatments until removed, or call Surrey Jet Washing whom can use professional equipment to remove the stain.

Pre-treatment of lichen

Due to the stubborn nature of lichen on driveways and patios, it may be worth a pre-treatment to help remove them from the hard surface. Jet wash the surface level of dirt from the driveway or patio, this will reveal if there is any stubborn lichen underneath which are notoriously difficult to remove. A bleach product and pressure washer will be the most effective method to remove the black spots. Before starting, fully saturate nearby bushes, grass, and plants with water. Use your PPE including gloves, goggles, and waterproof body suit.

Water the area sufficiently and use a bottle of bleach found in supermarkets, apply a generous amount of bleach to the blackspots and use hard bristle brush and scrub in; this allows the bleach to penetrate through the black spots to their ‘roots’. Allow to sit for half an hour and spray with water regularly if it starts to dry out which It often does in the summer. Then use your pressure washer to remove the black spots. Be patient as they are notoriously stubborn and try several applications until fully removed. Ensure this is done regularly as the longer they are on the surface the harder they are to remove. If the issue persists the patio or driveway will need professional help, with the use of a hot pressure washer which will make light work of the stubborn organics on the hard surface.


To conclude it is a good idea to apply pre-treatment to cleaning your patio, driveway, or other hard surfaces. This will help you remove the most stubborn, weeds, oil, or lichen. The best method depends on the type of intrusion; for weeds saltwater mix is advised, for oil is dish soap, for lichen is bleach. You may need to make several applications for stubborn marks. As always used appropriate PPE and consult Surrey Jet Washing if the problem persists.