Weeds pushing through grout - Weeds pushing through grout

[Z-GrimV]

Hi,

I've laid around 20m2 of Vietnamese blue stone and used a grout to fill the all the gaps.

I've now getting these crazy darn weeds, that almost like asparagus, pushing there way up through the grout.

I could not find anything on weed prevention for weeds pushing through grout. The seems weeds are also taking hold on the lawn. Any suggestions on how to resolve this nightmare? How to treat a weed that is dislodging all the grout?

[lutonlagerlout]

sounds a bit like japanese knotweed
a picture would be helpful but weeds should not be growing through a patio
LLL

[Z-GrimV]

Ello,

Here is some pics I uploaded to flickr.

SET LINK
Weeds

[Pablo]

If it looks like Asparagus then it's a weed called Mares Tail or Equisetum to be botanically correct. What you're seeing is the young growth which will eventually open out into a feathery shape abpout 80cm tall. It's very easily dealt with here but I'm not sure if you can source the same chemicals in the Netherlands. I use one called Agritox 50 at a 4 part water 1 part chemical mix and apply with a sprayer and it has never failed to work first time. It's also lawn safe and will kill all weeds in it at a 125ml:16ltr water mix but if you continue to mow it then it'll not be a problem in you lawn. You could try phoning a local agricultural or greenkeeping supplier and they'll be able to source a similar product once they've googled the active ingredients and it's uses. You may need to get a herbicide quallified landscaper to buy it and apply it though. Good luck email me if you need to know more. Try this link below for a thred I started last year about it.
http://ext.pavingexpert.com/cgi-bin....es+tail



Edited By Pablo on 1335893163

[Z-GrimV]

Thanks for the feedback. If you see my second post, you can see some examples of what is happening. The weeds examples are as you mention, starting to feather out after those pesky points have pushes through.

How would you go about treating the paving as they are pushing through from below the grout? If I apply the chemicals (or have it applied professionally) how can I ensure it permeates through the grout to the weeds? Does it mean de-grouting?

[Pablo]

Spray whatever foliage that is above ground and it'll draw the poison into it's roots for you so there's no need to lift or re grout anything. I would let it grow a bit further though so that there's more foliage to get the chemical onto.

[ken]

When ever I see mare’s tail growing though existing paving before I replace it, I treat it with weed killer two weeks before we start the job, then try and excavate all roots and use a good geo textile under the sub base. But I guess a DIY’er wouldn’t know about these tricks of the trade.
Hats off too you for having a crack at laying your own patio tho!
At least it’s only mare’s tail, and not that Mexican foxtail bamboo, that’s an absolute tw@t to get rid of.

[Z-GrimV]

Thanks all for the tips and advice. First time I laid paving stones. Some things we learn the hard way, eh Well at least I know for the next time to treat the area first.

Some people say that vinegar also works for this type of weed. Is that correct? My wife also pointed out that Vietnamese Blue Stone can be damaged by acidic liquids. Any thoughts on this?

[Pablo]

Your stone looks like limestone which is very easily damaged by anything acidic so don't use vinegar which I seriously doubt would work anyway.

[dazbrandy]

i was told that marestail has a waxie protective coat so spraying it will not kill it you need to break part off the plant in order for the chem to get in to the plant and kill its root system.

[Pablo]

That's what folk do when spraying with Glyphos but it's only partially successful and the plant usually starts to develop a resistance to it so it's best not to spray with it because it becomes stronger and chemical tollerant over time.

[Z-GrimV]

Pablo, Just to get clarification on the lawn comment from above. It's a relatively new sod that is always showing multiple patches of the evil weed By mowing regularly it shouldn't worry about using the chemical Agritox 50? Also, is this safe to use with a garden where kids play?

[Pablo]

With regular mowing it won't grow any higher than the grass and will eventually give up. It's safe for humans and is used to kill weeds in dairy cow pasture but I'd keep them off it for 36 hrs after spraying and also wear gloves goggles and a mask when using it whilst also covering all other exposed skin.