# Best option for bulk weedkiller



## St Evelyn (Mar 15, 2019)

Inspired by Rian P's thread about cleaning algae from walls, I thought I'd ask for recommendations for weedkiller.

I put down 100m2 of resin bound gravel a couple of years ago and we've a number of weeds coming up through. Now, in theory, these should just be seeds that have landed on the surface and germinated so can easily be pulled out, but I don't like the idea of leaving any root behind so would like to spray them with weedkiller and leave them a few weeks before trying to extract them. We also suffer with lots of weeds where the public footpath meets our wall on 2 sides of our garden.

I've tried the usual suspects from B&Q (Roundup, Resolva etc), but even buying a 5L dispenser doesn't seem to last very long or kill off some of the stronger weeds. Instead, I bought a 16L backpack sprayer from a sample sale at work and figured I'd fill it with some super-strength weedkiller and be able to spray them without bending over. 

So, does anyone have any recommendations for a decent weedkiller to put in to it please? I'm intending to use the sprayer to dispense BAC-50 (likely diluted 1:25ish) in a few weeks' time as per Ross @ Anachem's advice on Rian's thread; any suggestions for a suitable solution (boom boom) please?


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## AndyN01 (Feb 16, 2016)

The active ingredient is Glyphosate.

AFAIK Most stuff in B&Q etc. is about 9g per litre 

Look for something that has Glyphosate at a higher concentration and dilute it down.

Be careful as some is so high that it is classed as a professional product and requires the user to comply with the DEFRA/HSE Code for the Safe use of Pesticides.

Happy spraying.

Andy.


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## GeeWhizRS (Nov 1, 2019)

Have a look for Rosate 36. Takes about 2 weeks to work but it does work. You’ll need to reapply through Summer months. 
I use this then I use a big burner to shift the shrivelled remnants to tidy up.


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## DTB (Dec 20, 2017)

Any glyphosate based weedkiller will work on pretty much everything that you're likely to encounter. Gallup, Roundup, etc, although you might find some of the garden centre Roundup products have a different active so check it's not some sort of acid. You can buy Gallup on Ebay.

If it's not lasting long, maybe you're applying too much. Doubling the strength or spraying it until it runs off the leave won't kill the weeks any quicker, it will take a week or more for it to work through the plant. Just a very quick pass with your sprayer on a very fine spray is sufficient though. Do bear in mind that no weedkiller is particularly effective on tiny little seedlings, you do need to wait until there is sufficient leaf to absorb the product. Also, it's less effective in colder weather then plants are dormant or growing very slowly.

Dilution rate of 20ml per litre of water will do the job. Please don't mix up 16 litres worth at once though, that's enough to 800 m2 at the recommended rate (unless you have 800 m2 to spray of course...)


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## President Swirl (Oct 23, 2011)

Probably obvious mate, but be very careful when mixing glyphosate. I'd be surprised if it's available in neat form commercially.
Make sure you're in a well ventilated area, and take further respiratory measures. Also be sure that none drifts into surrounding areas, and be sure it has time to get to the root before any rains. (24hrs, min). Any tiny amount getting into a mains water supply or aqua fir could be damaging and costly.

Not being a doom-monger my friend. Most stuff from Notcutt's et al, should be fine. Check the label to see if it's a total or selective.


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## galamaa (Aug 3, 2014)

Pure winegar and thats it ( but it kill everything)or order from Poland(out of europe) substral weedkiller. Really good product!


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## Vossman (Aug 5, 2010)

Glyphosate based products are the best but the EU banned them in anything that would work on weeds lol. 

Do you know a farmer or someone with a smallholding? They might be able to help you out with it. You won't be able to buy anything that is really "effective" yourself. 

Some people swear by vinegar and washing up liquid, the vinegar kills the weed and the washing up liquid enables it to cling onto the plant but personally I never had any luck with that, I use a burner on my drive but they still come back.


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## St Evelyn (Mar 15, 2019)

So, I've gone through the suggestions and most seem to be glyphosate-based - Rosate 36 (now re-branded as Rosate 360) has 360g of glyphosate per litre, 40x the strength of the high street weedkillers.

I've ordered some Gallup XL from eBay (£26.50 for 5L delivered) so will give that a go when the weather warms up a little and the weeds start growing. Although I wanted to use the backpack (to save me bending down), I will heed the advice given and just make up a litre or two and use some other bottle or sprayer to apply it. 

Thans for everyone's hep, it's much appreciated. :thumb:


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## Mugwump (Feb 17, 2008)

Whilst question marks have been raised relating to glyphosate (mostly without any real evidence to back them up), glyphosate has NOT been banned by the EU or the UK (current approval period is up to the end of 2022).

As it is purely a herbicide, it has no other purpose beyond using it on 'weeds'!

It is also the least potentially harmful to humans of any herbicide that has been in common usage, and there are no special precautions necessary when using it as directed by the label beyond basic PPE such as gloves and a faceshield, which should always be used with any pesticide.

Due to the cost and data required for approval, a lot of previously available active ingredients are no longer available to the 'garden' market, so most of the total weedkillers that you get from a garden centre will be glyphosate based - Roundup, Resolva, Rosate being the most common ones.

The important thing to remember is to use the specified rate and that you only want to spray a 'mist' over the leaves - so that the drops stay on the leaf. If you spray to the point of run-off, most of the active ingredient goes on the floor from where it does nothing at all.

Above don't buy the ready mixed stuff - you are paying a lot of extra for water. Buy the concentrated version and mix it yourself (most of them come with a measure of some description).

The garden centre type stuff is indeed about half the active ingredient that will be found in commercial strength formulations; and the ccommercial ones also contain adjuvants to help it spread and stick to the leaf - it is some of these adjuvants that are potentially more harmful to health.

Whilst it is a legal requirement for users of agriculture/horticulture approved products to hold the relevant certificates of competence (PA1 for handling, and PA6a for using a handheld/knapsack type sprayer), there is plenty of the commercial grade stuff available _'you-know-where' _, and I would suspect there are a fairly substantial number of containers of such stuff in garden sheds up and down the land.


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## Mugwump (Feb 17, 2008)

St Evelyn said:


> I've ordered some Gallup XL from eBay


5 litres should last you several years - probably only need 30-40ml per litre of water to kill almost any weeds you have to deal with.

Not sure why you wouln't use the knapsack - you don't have to fill it right up, and glyphosate washes out fairly readily with plain water - half fill, lid on, swill it about, tip out; repeat; then part fill again and pump out through the nozzle to clean the pipework and lance.


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## Matt_H (Jan 1, 2007)

Along the same lines, can anyone recommend a quick an easy way of moss killing on block paving?


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## fatdazza (Dec 29, 2010)

https://www.detailingworld.co.uk/forum/showthread.php?t=424835


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## ridders66 (May 24, 2019)

Matt_H said:


> Along the same lines, can anyone recommend a quick an easy way of moss killing on block paving?


Algon without doubt. Many swear by Jeyes fluid, but it absolutely stinks.


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## ridders66 (May 24, 2019)

I don't know how much truth there is in this, but I have heard from many people that the best weedkiller they have used is AdBlue. Bought in 20 litre containers from a commercial vehicle dealer, it is remarkably cheap compared to weed killer. Modern weedkillers are weak compared to what they used to be like, EU legislation ruined it. Or, if you know a landscape gardener or someone who works at a garden centre, they have access to much stronger weedkillers than can be bought over the counter, they have a license to buy the professional products.


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