SPARTAN33 Registered User
#1

Hi Folks

Hope someone can help, havent cleaned the patio Indian Sandstone paving in the back garden in a while so tried to start today with no great visible improvement, I used a cleaning product for paving areas and alot of scrubbing with not great reuslts. My problem is small groups of small black spots that seem to really discolour and are taking over the paving stones I think they might be lichens theres no flower on htem though just like kind of like ink spots they are more like stain spots on the sandstone slabs, Was wondering if there is another product I could use to get rid of them and clean up the paved area or would a power washer do the trick. Im sick of rubbing and scrubbing and getting no where. Those black spots or stains are hard to shift.

Any help on these would be greatly appreciated

treesireland Registered User
#2

sandstone is porus , algy and stuff will penatrat the stone. the only way to remove stains is by removing 1mm of the stone or more. if u have new sandstone and its clean and dry there are some products out there that seel the porus stone to prevent staning like u talk about. but i find these products make the sandstone slipy and do not last the test of time.

dardevle Registered User
#3

.


http://www.pavingexpert.com/maintain_02.htm#aml

.
.....the most helpful of websites when it comes to paving.



.

1 person has thanked this post
treesireland Registered User
#4

pardon the pun, the site u put up leves no stone unturned, i will keep the name it will be very helpfully to me thank u very much.

nanot Registered User
#5

www.nanotechsolutions.ie


Blackspot is hard to remove but desalin available from above or chlorus which is usually available at a farmers coop

Discodog Registered User
#6

Don't believe all you read. Pavingexpert recommends Glycophosphate for moss when in fact it will only kill a few types of moss.

It is critical to seal it as soon as it is cleaned.

dardevle Registered User
#7

.



actually they recommend glycophosphate as a standard moss killer instead of one containing ferrous sulphate which will cause colour change in the paving... when you take this in the context of all the advice given it is sound...they also have a great deal of information on sealing paving if you read further on


....

Discodog Registered User
#8

Glycophosphate wont kill most mosses !. It is a systemic weed killer which translocates & depends on quite a large leaf area which mosses do not have. It would kill a sphagnum moss as this has a relatively large leaf. The main moss killers are based on tar acids. Armilartox is the most common but Jeyes Fluid is basically the same & much cheaper.

The main problem with discolouration can come with people using bleach which is a very effective moss killer but you have to be very careful with dilution & overspray.

dardevle Registered User
#9

Discodog said:
The main moss killers are based on tar acids. Armilartox is the most common but Jeyes Fluid is basically the same & much cheaper.

.



this from the paving expert website....

"There are mosskillers that do not rely on ferrous sulphate. Armillotox is one such product that is popular with gardeners as it has pesticide properties that got it into trouble with the EU for a period, but it is now sold as a cleaner, rather than a pesticide. Jeyes' Fluid is another, similar product that may be more readily available. As far as is known, neither of these products has a deleterious effect on the paving itself."

seems like sound advice when you read it!!(the complete article that is)


.

Discodog Registered User
#10

I was questioning their advice re glycophosphate !. If you want to use it then go ahead.

dardevle Registered User
#11

Discodog said:
I was questioning their advice re glycophosphate !. If you want to use it then go ahead.



and i was questioning your effort to pick things out of context to try and find fault with......personally i would follow their best advice which is "that most moss can be removed by sweeping and/or scraping".




.

Discodog Registered User
#12

Scrape away. I have 100 sq yds of mossed block to do tomorrow - I would be scraping for a week. Recommending a product to kill moss that will not kill most mosses is not taking something out of context & it didn't take a lot of effort to spot !.

But as the author & I kind of know each other as we both post on a Pro Gardening forum I will ask him, just to satisfy my own curiosity. As someone who has been in this business for over 20 years I know that opinions vary. He will be pleased to know that his advice is being so avidly protected.

dardevle Registered User
#13

....

so perhaps as a paving expert you can answer this.....what can you use to remove moss?... that does'nt contain ferrous sulphate, is not armillotox, or jeyes fluid, or bleach, but you are still set on using chemicals...the site goes into each of these methods in depth but says if you are still dead set on using chemicals... then - pathclear or glyphosate( a herbicide that kills some but not all mosses) will do the job without re-colouring the paving....not exactly a recommendation for using round-up would you agree?


btw i have no vested interest in the site "pavingexpert" but i have found it useful for many years, just like tens of thousands of other people,






.

Discodog Registered User
#14

I am not a Paving expert. I design & maintain gardens. I will not be treating the drive tomorrow as rain is expected during tomorrow night. Every driveway is different. This one has good kerbing & drainage so I will use Jeyes Fluid.

Moss/weeds should be a major consideration when selecting paving. The modern blocks have a bevelled edge that creates a v shaped trough that is perfect for moss & makes it really hard to remove. Once the moss is dead I will use a powered rotary brush to remove it.

Copper can be effective. When i was working in the West of England we fitted copper wires to old stone slate roofs. Apparently it is a very old idea & relies on rainwater to dissolve tiny amounts of copper which washes down the roof. The idea has been copied by a company who make copper caps for roof ridges.

I am thinking of incorporating something similar into the next driveway.

dardevle Registered User
#15

This one has good kerbing & drainage so I will use Jeyes Fluid.
quote]

excellent choice...as recommended by paving expert




.

Want to share your thoughts?

Login here to discuss!