Glyphosate - how quickly can I replant?

[205alive]

If I use a glyphosate based weedkiller to kill off a weedy lawn and re-turf it, what's the minimum time I would have to wait? I've stupidly ordered the turf without taking into account the dying off time of the old weedy lawn, the neutralisation of the weedkiller by the soil, and the fact that the turf may be then past it's best by the time I actually lay it.

If I spray now, this evening - will the lawn and weeds die off by, say, Sunday or Monday at the very latest, and will the weedkiller be neutralised?

If the new turf isn't laid, is there anything I can do to prolong it's life by a few days?

[richyb]

I am pretty sure there is little trace after a few days. It does depend on the concentration you have used.

[Simpo Two]

Glyphosate is a total non-residual herbicide; ie it's broken down in contact with the soil. However as it is a translocated herbicide, it does take 7-10 days to work. See instructions and all that.

By Sunday or Monday the product will certainly be neutralised, but the weeds will look exactly the same.

Turf needs water and light to live so you'd have to unroll it all and keep it watered... not an option I suspect. Suggest you nip out and get some Weedol, which is a total non-residual contact herbicde and works in 24-48 hours.

You're not planning to lay the turf on the old lawn are you?

[Shaolin]

Hire a rotavator drive it round a few times and rake up the remains of the grass.

[racing green]

Shaolin's right the weedkiller will not work quickly enough. Rotovate thoroughly and rake all the rubbish out. This will give you a much better bed on which to lay your turf anyway.

[wolf1]

On a similar track, what's the best weedkiller to completely kill off a lawn prior to groundwork. Available to the public that is.

[netherfield]

Glyphosate (Roundup). As stated above it needs time to work.

I use the stuff from an agricultural merchants.You really need 24 hours without rain after use,so watch the weather forecast.

[205alive]

Simpo Two said:

Glyphosate is a total non-residual herbicide; ie it's broken down in contact with the soil. However as it is a translocated herbicide, it does take 7-10 days to work. See instructions and all that.

By Sunday or Monday the product will certainly be neutralised, but the weeds will look exactly the same.

Turf needs water and light to live so you'd have to unroll it all and keep it watered... not an option I suspect. Suggest you nip out and get some Weedol, which is a total non-residual contact herbicde and works in 24-48 hours.

You're not planning to lay the turf on the old lawn are you?

Planning to kill off the old lawn, rake up remaining matter, dig over, rake again until fine, then lay the new turf. Not going to lay directly on to dead turf without removing it first.

I do have enough space to roll out the new turf so may feed and water it for a week until the glyphosate has worked. Thanks for the clarification.

[205alive]

racing green said:

Shaolin's right the weedkiller will not work quickly enough. Rotovate thoroughly and rake all the rubbish out. This will give you a much better bed on which to lay your turf anyway.

Yep, will do that except for the rotovation part - it's a relatively small lawn so shold be able to manage without one.