Things You'll Need
2 cups lemon juice
Acrylic bristle brush
Moss, squashed leaf matter and plant debris can cause ugly and unsightly marks on your concrete or paved driveway, but palm tree stains are a particular killer. Palm tree leaves and fronds leave black and sticky debris on the concrete and bricks of driveways, and can be particularly difficult to remove. Palm trees are also prone to shed more than the average tree due to their heavy branches, which means even more cleaning up for palm tree owners.
Use your pressure hose to wash down the surface before you apply any chemicals. Choose a clear, sunny day to clean your driveway, not only so that it dries quickly during treatments, but also because it will help you to better see the palm tree stains in the sunlight. The stains are usually dark brown or black, but can take on a silver slick if they have had car oil and gas added to the mix.
Pour 2 cups of lemon juice into a large bucket with half a gallon of white vinegar. Mix them together with a wooden spoon.
Pour the solution sparingly onto the affected parts of the driveway and scrub with the acrylic bristled brush. You will notice palm tree plant matter and moss debris are coming away from the driveway surface — you do not need to scoop up the matter as you go. Keep doing this until you run out of solution. Apply this solution only to the areas of the driveway in which you can see palm tree matter is staining the surface. If you have leftover solution apply it to unaffected parts.
Spray the areas of the driveway that you have scrubbed using the vinegar and lemon juice solution with the pressure hose. Then go back and spray the entire driveway.
Wait for the driveway to dry. Assess the stains that you worked on with the vinegar and lemon juice solution. If they persist, reapply the same solution and scrub again. Reapply the pressure hose and reassess. Stubborn palm tree stains may often take two cleaning cycles to completely clear up.
If you find that the solution is not working well enough after two applications, add 2 cups of bicarbonate of soda to the mixture and try again.
Keep children and those with allergies away while you are applying the cleaner and scrubbing.
If your driveway is made of painted concrete a high pressure hose may actually lift some paints from the surface. Either use the hose on a lower pressure level or use a normal garden hose to complete the task instead.