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Weed killing before turfing

Hi there I have a problem,I have had a wall built and the soil got moved everywhere and it has weeds growing everywhere,I was planning on killing all the weeds off and levelling it all off them turfing the lot but,will the weed killer affect the turf from growing even if I leave it a few weeks after treating it all thanks 




  • LeadFarmerLeadFarmer Posts: 1,464

    When I last laid a new turf lawn I used weed killer on the weeds and waited a few days for it to have effect before lifting the turf. I then raked it level and left it bare soil for a few days to see if any weeds re-emerged, and treated accordingly with weed killer again. This allowed me to also see if any pooling formed when it rained, and I could fill any low areas with soil, before finally laying new turf.

  • DovefromaboveDovefromabove Posts: 86,869

    There are basically two types of weedkiller - the ones that linger in the soil and the ones that don't - in order to plant after using weedkiller you need to use one containing glyphosate.  This takes a couple of weeks to kill the weeds, but after that you can plant/sow again.

    Spray the glyphosate and leave the weeds until they turn brown before uprooting them.

    Then you can prepare your ground for the turf. image

    Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.

  • Hi there thanks for the info much appreciated would it work with vinegar salt and washing liquid ?

  • DovefromaboveDovefromabove Posts: 86,869

    Use a proprietory weedkiller witht the active ingredient glyphosate - use according to instructions on the pack.

    Using salt will contaminate your soil and nothing except asparagus will grow.

    Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.

  • Hi I am planning on laying turf soon. The garden was previously block paved so very compacted. So I'm also going to Rotavate.

    As I understand I need to weed it, rotovate it and fertilise it before turving. In what order should I do this and how long should I leave before the next stage? 


  • If it was previously block paved, I guess not much is growing at the moment. In that case I would rotavate when the ground is a bit drier, break any larger lumps with a spade, level with a rake, and then roll with a garden roller. I would then give it a light rake to break up the surface, then leave it 2-3 weeks before seeding (probably mid-April, when the ground is above 10 degrees).

    In the 2-3 weeks before seeding, weeds will grow. I would remove them by hand or, if there are lots, spray with a glyphosphate weedkiller (Roundup) and leave it another couple of weeks before spreading grass seed (to allow the weedkiller to break down). You may need to repeat the process of raking to level, rolling, then lightly raking to break up the surface.

    If weeds or grass are already growing in the area, whether you weed before rotavating depends on the plants. Most small weeds would be killed by rotavating, but others will persist (and breaking up the roots could spread the problem).A picture might help.

    As for fertilising, it depends on the quality of the soil. If it's in poor health you may want to rotavate in some soil conditioner or possibly rotted manure. Or add fresh topsoil on top of the patch to be sown. Regular family lawn mixes are pretty resilient though; ornamental lawns can be more fussy. Last time I sowed a lawn I spread a bit of Growmore when seeding (general purpose feed) just to give it a bit of something, but it probably wasn't needed.

  • Thank you. I am going to be using turf. Is the advice the same? 

  • Yes, the prep work is all the same.

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