Cleaning leaf stained slabs

[chequers]

Hi
We are laying the last of our 450mm panache textured slabs but they are quite heavily stained from.being kept stored under trees and have changed from white when new
The only issue is that there are plants everywhere
Tried power washing individually no chance ,leaf stain sap etc will not budge
Any ideas
Thanks

[rajan2004]

Try Oxalic Acid - in the discoloured sandstone paving thread, I posted some images of my yellow stained path. We used Oxalic acid and instantly the stains have lightened.

I'm planning to apply it a few more times until the stains disappear completely. We also have leaf stains and I'm pretty confident this will remove them too.

Once it's all cleaned up, my plan is to get the whole path jet washed then sealed (once the weather is better, around easter time) so it doesn't stain so easily.

You can buy the acid from eBay - it's only about £9 a kg

[RAPressureWashing]

You don't need to use Oxalic acid for this, have a look at the main site, stain removals page, and search for the fruit & berries entry, that mix on there is all you will need if it is just leaf tannins, just follow the instructions properly

[London Stone Paving]

We always use Lithofin Outdoor Cleaner to remove any organic markings........never failed us yet!

Steve

[chequers]

Thanks all ,had a read of the products being recommended but They look like they would harm destroy the plants surrounding ?

[RAPressureWashing]

If you take care, and with low lying plants, water these first so they are not thirsty, you can always cover with polythene while working then remove and water again. you should be fine. Along side grass, you won't kill this unless your run-off is straight on to it, you might get a bit of burn or scorch to the edge, but it will grow back, unfortunately when grass it tight to a paving this can & will happen. You really just need to take care when applying chemicals, I'd watch out for wind-drift as well. I clean day in day out so all do-able, just stop and weigh up the hazards first.