Getting rid of moss/green on flags

[con1_uk]

Hello,

I have looked around the forum for an answer to this,

I have Indian stone flags in my garden and they get very Green very quickly, my approach so far has to power wash the flags every few months or so but I understand this isn't too good for the stones.

What is it that causes this Green? I don't have many trees around just a few small bushes around the flagged area.

My local shed told me to use some kind of spray but I wasn't sure if this would work, does anybody have any experience of this spray? Is it safe for the kids and pets? What about the plants will it get in the soil?

Thanks.

 

[con1_uk]

Any help please?


I want to get this done over Easter.


Thanks.

 

[Thermo]

its algae that will form on any natural surface, especially if it is in shade. You can use a power washer, but it has a habit of blowing out the pointing. A less messy way is to use a stiff broom and a bag of sharp sand to scrub the surface with. You can seal it with a sealer, but make sure you test an area first as not all sandstones like the chemicals

 

[WabbitPoo]

The problem with natural stone flags is that they tend to be quite un-even, hence water can settle into the hollows, even when laid on a slight fall. They can be a pig to lay, as a result They can also be quite porous, or at least have rough surfaces which hold the dampness. Even when laid right, and in sunshne, they are prone to greening up.
The pressure washer wont damage the slabs, but as Thermo says, the pointing can come loose.

In general, follow Thermo's advice. I always do!

 

[Thermo]

awhucks, i make it up as i go along, im really a 92 year old granny sitting in a home knitting!

 

[WabbitPoo]

yes, i thought so.

 

[con1_uk]

Thanks for the replies so far,


Is there nothing that I can spray on to clean it? Also once cleaned will a sealer keep it clean?


Ta

 

[Thermo]

chemicals an natural stone dont mix well and can stain it. a bit of elbow grease works well. a sealer will help, but you will not stop nature. all hard surfaces in gardens need maintenance of some sort to keep them looking good

 

[con1_uk]

Thanks so much for your replies,

Been out today with the power washer and it looks 100% better.


I have found a web site which is very good for paving type questions am I allowed to post it here?

 

[Thermo]

paving expert by any chance?

 

[con1_uk]

Thats the one,

 

[dextrous]

awhucks, i make it up as i go along, im really a 92 year old granny sitting in a home knitting!

We've worked that one out ages ago