Methods to clean slippery York stone flags - suggestions please

BooJewels

I just wanted to report back on this matter, just in case anyone searches and comes upon it.

What I did in the end, was a two prong approach.  As I had a guttering issue too - I found a local exterior cleaning company who turned up the morning after I rang them, treated the problematic path with some chemical, then sprayed it with an industrial pressure cleaner.  Looked fabulous when they'd done.  They went up a ladder and cleaned out and flushed all my guttering.  They took all the gunk away with them and cleaned up after themselves.  I was extremely happy with the results.  

After a few days, when it was dry for a while, I applied Wet and Forget to the more critical stretch of path initially, as I wasn't sure how far it would go and just made a 6 pint batch.  I had just about enough left to spray a garden bench and table and you can see already, after about 10 days, how it has already improved the bench itself - which was green - I didn't really do it that thoroughly as it was running out of liquid.  The improvement there was visible the following day - the concrete took a little longer and the overspray itself was enough to improve it visibly.  The other photo is a bit of moss at the edge of the path that I'd sprayed and which is clearly dying back.

I was hoping to do more today, but it's just remaining so damp, the ground just isn't drying enough - especially where I'd swept leaves, it was sodden.  My large spray bottle worked well and I'll be very happy if I can do this a couple of times a year to keep it at bay.

Thank you for the assistance.  I was very happy today when I went out and saw those two areas.

gozaimasu

You mentioned the pressure washer is messy - maybe try a patio cleaner attachment if you fancy trying again in future to save yourself money. Hopefully your wet/forget stuff will stop it getting as bad as it was.

BooJewels

gozaimasu said:

You mentioned the pressure washer is messy - maybe try a patio cleaner attachment if you fancy trying again in future to save yourself money. Hopefully your wet/forget stuff will stop it getting as bad as it was.

Thank you. I presume that is the flat cylindrical attachment to cover the jet end?  I did find one of those, if it is, so I will give it a go.

I also mentioned earlier that I wasn't sure I'd be able to get it up the cellar stairs - but having actually got it out, I realise that it's possibly lighter than my handbag, so that's not going to be an issue either - it's much dinkier than I'd visualised from memory.

I'll certainly try it myself at some time - I'm on a steep learning curve at the moment, but rapidly acquiring new skills.  I'll give it a try when my son is here, as I may need to set up a system, or adapt a tool, to help me get the hose in position etc. on my own, as I have to pass it over a tall wall and through a tree.