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Black plastic sheeting to kill weeds?

Posted 14th Aug 2013
We’ve recently moved into a new house where the previous owners hadn’t touched the garden in over 14 years! So as you can imagine it’s in a complete mess with weeds and shrubs everywhere. I cut most of it back so you can walk over it but it really needs everything killed and pulled out including all the grass so that it can be started fresh.

I put weed killer down and waited a couple of weeks before starting to tackle the weeding, but it’s taking forever to even clear a small section and I’m running out of time before we lose the light in the evening and the warm weather.

I read somewhere that you can put down black plastic sheeting over the area you want to kill. If say I did this now would everything be killed and wasted away by early spring? In a perfect world I would pull the sheets back and see just soil 

Or is there something else I could try?
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If you just cover it with black plastic it will not kill all the weeds they will be dormant and some will still need removing when you remove the plastic in Spring. If you have no time turn the soil over so the roots are on top cover with the best weedkiller you have and then cover with plastic, this will kill more of them but weeds are tenacious and so you will still have a few when you remove the plastic. You can buy special material for this cover but it is usually done when the weeds are removed to stop any coming back, unless you have knotweed which is treated differently. good luck
When I had a really big bad garden to clear years ago I hired a Bobcat digger for the weekend and turned what was going to be a terrible hard job into a fun one. Don't know a lot about gardening but I did see a film a few years ago about allotments and a guy on there cleared his using plastic sheet.
Don't put weedkiller on cut-down weeds and then cover - it won't work. Modern weedkillers are systemic - you spray them onto the leaves and the plant absorbs and transports them down to the root system where they kill it off. For this to work, the weeds need to be growing strongly and have a large leaf area to take the weedkiller. It's coming to the end of the growing season now so most of what you've cut down isn't going to grow enough to take weedkiller. Systemic weedklllers do take time to work, it's not an overnight solution.

If you're not going to do any more work this year, then cover it but not with plastic. Whatever you use needs to exclude light but allow water to pass through and the soil to breath. You can buy cheap weed suppressing membrane from pound shops, Wilkos. etc. Or you can use flattened cardboard boxes. Weight them down very well so they don't take off in the first gust of wind. Doing this won't kill all the weeds completely but it will stop more growing this year and hold back new growth in the spring until you can dig it over and get the roots of any perennials out (couch, bindweed, nettles, brambles etc). If you have Japanese Knotweed that's a whole other ballgame and you need professional help.
Edited by: "deleted701517" 14th Aug 2013
Thanks for the advice all.

Would just turning the soil over, without removing the weeds, then covering with a membrane be enough to help kill the weeds?
It's excluding light that helps to kill the weeds although some of the tougher perennial weeds will survive. In your shoes, I'd cover it as it is which will stop any more growth this season and over the autumn and winter weaken/kill some of the existing weeds. Then, when you're ready in the Spring, uncover and turn it over removing the roots of perennial weeds. This way, you only have the effort of turning over once which is best done just before you're ready to plant.
Easy. Spray the area over with a bit stronger mix of concentrated (not ready-mixed) "Roundup" than recommended. Yes, Roundup is also 'systemic' but a stronger mixture will sort out the men from the boys! Then just throw an old carpet down. It'll stay in place better than anything else due to the weight. Better once it gets wet. Then, when the job is done just roll that baby up!

I'm afraid if you're looking for an 'overnight' cure to your problem, there's only one answer. Hard graft. Dig, dig, dig. One other thing - for membrane, don't go cheap. This might not help but if you have a farm nearby, ask if they have any empty 2 tonne fertilizer bags. I buy these locally for 50p a pop and they are a better membrane than you'll ever buy from a retail outlet. Cut them open, flatten them out and; as they say; job's a good-un! Just make sure whatever was in them previously isn't harmful, of course.

Good luck, and I hope you enjoy your new home and garden.

Regards, Phsy.
I have been putting down concentrated Round-Up, I will put down a stronger mix next time it's dry.

Carpet is no good, it's quite a large area. But I will look for a decent membrane to put down, probably for the next 6 months.
I would not use carpet. I've had to deal with it on my alltoment and it's horrid stuff, it's prohibited on many sites now. Synthetic carpets leach chemicals into the soil. When they (or woollen carpets) start to break down you get lots of horrid fibres left in the soil and they are unbelievably heavy to remove when wet and caked in soil.

I'd also advise against using pesticides in any way other than that advised on the label - the safety instructions which the dilution rate is part of are there for a purpose. Spraying cut down weeds at this time of year is a waste of your money and your effort. Any systemic weedkiller needs the plant to be growing to work, no matter how strongly you apply the mix.

Edited by: "deleted701517" 14th Aug 2013
anyone know what this is?
i assume its a weed as seemed to be vigorously growing in wild but seemed to attract loads of bees/butterflies

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thanks, thought you'd know
googling 'bushy yellow flower weed daisy' got me nothing^^
doesn't seem like anything should encourage in garden then i guess

thanks, thought you'd knowgoogling 'bushy yellow flower weed daisy' got … thanks, thought you'd knowgoogling 'bushy yellow flower weed daisy' got me nothing^^doesn't seem like anything should encourage in garden then i guess

Er, no. There are better options for the beasties. My golden rod (ooh, er, Mrs oO) is smothered with bees and butterflies at the moment.

Er, no. There are better options for the beasties. My golden rod … Er, no. There are better options for the beasties. My golden rod (ooh, er, Mrs oO) is smothered with bees and butterflies at the moment.

cheers listed under beginner on bbc site too - my kind of plant.
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