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Killing thistles in lawn

Wilson73Wilson73 Posts: 136
edited July 2020 in Problem solving
I have lots of thistles in my lawn and have bought Roundup concentrated root killer to paint on with a brush,can anyone tell me if I will still manage to seed my lawn after doing this?It was my view that the weed killer would just effect the thistle.I was going to pull them out with a little tool,but after reading about thistles rooting laterally and that when that root is snapped it will grow back straight away,hence me deciding to use weedkiller
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  • K67K67 Posts: 2,506
    We seem to be going over the same things with your lawn.
    Have you used the Evergreen 4 in 1 yet and used it correctly. It takes time to work. Then if you still have weeds you can try the correct weedkiller for lawn weeds and spot treat.
    Then you wait at least 2 months then you can reseed. There is no point doing it earlier as the seed won't germinate if it's too hot and dry.
  • Wilson73Wilson73 Posts: 136
    edited July 2020
    K67 said:
    We seem to be going over the same things with your lawn.
    Have you used the Evergreen 4 in 1 yet and used it correctly. It takes time to work. Then if you still have weeds you can try the correct weedkiller for lawn weeds and spot treat.
    Then you wait at least 2 months then you can reseed. There is no point doing it earlier as the seed won't germinate if it's too hot and dry.

    I have the 4 in 1 the problem revolves around thistle which I've heard it won't kill,I was hoping somebody would have experience of what product does kill thistles as I can't be the first person with that problem.I would still need to know which weed killer to safely spot treat as I'm going to reseed afterwards,so I don't want to waste my time sowing grass seed if it wont germinate after using the wrong weed killer.
    At the moment I'm feeling like concreting the entire garden :(
  • LoxleyLoxley Posts: 5,698
    edited July 2020
    If you manage to not drip any glyphosate on the lawn, the existing grass will not be affected. It only kills plants whose leaves it touches. If you are reseeding the lawn, you may as well use a spray though, as you will be getting rid of the grass anyway. You can certainly reseed by the time the weeds have been killed. It doesn't stay in the soil - at least not in a way that affects future planting. Apply glyphosate in the morning for best results - makes a big difference.
    "What is hateful to you, do not do to your neighbour". 
  • Wilson73Wilson73 Posts: 136
    Loxley said:
    If you manage to not drip any glyphosate on the lawn, the existing grass will not be affected. It only kills plants whose leaves it touches. If you are reseeding the lawn, you may as well use a spray though, as you will be getting rid of the grass anyway. You can certainly reseed by the time the weeds have been killed. It doesn't stay in the soil - at least not in a way that affects future planting. Apply glyphosate in the morning for best results - makes a big difference.

    Hi thanks,my terminology doesn't help me at times,by reseeding I meant seeding the areas that are thin and those that will be bare after weed removal,as I have existing grass in place that I want to keep,but thanks for explaining how it works and the tip for the morning application.I think I'm going to apply it this weekend.
    I have spent the last 2 months gardening as a novice and I have enjoyed the results thus far,but it has been tiring as I'm a full time carer,so I already expend a lot of mental energy and I tend to worry about things going wrong and I can get a bit stressed,what ever happens I'm sure the lawn will recover anyway.
  • JennyJJennyJ Posts: 10,576
    I think you mean overseeding? Using glyphosate on your thistles will be fine but the grass seed is better left until autumn when the growth of the existing grass slows down. Otherwise it's difficult to cut the existing grass without disturbing the new seedlings.
    Doncaster, South Yorkshire. Soil type: sandy, well-drained
  • Wilson73Wilson73 Posts: 136
    JennyJ said:
    I think you mean overseeding? Using glyphosate on your thistles will be fine but the grass seed is better left until autumn when the growth of the existing grass slows down. Otherwise it's difficult to cut the existing grass without disturbing the new seedlings.

    @JennyJ yes that's it,I confuse myself on a regular basis :)I'm planning to apply the glyphospate tomorrow if it looks a sunny in the morning
  • ShepherdsBarnShepherdsBarn Posts: 401
    There is an old rhyme about getting rid of thistles ...
    'Pick them in May - they'll be back next day.
    Pick them in June - they'll be back soon.
    Pick them in July and they will surely die.'
    So you have about a week!
  • Wilson73Wilson73 Posts: 136
    I applied glyphosate today,at least the rain only lasted for 5 minutes.
  • ObelixxObelixx Posts: 30,090
    Was the rain before or after the glyphosate?   You need 6 hours of dry, sunny weather for the active ingredients to be absorbed and 2 weeks for it to work and, with a plant like thistles, you may need a second application in case some of the root survives and starts to grow again.

    Personally, I would have cut the thistles down and then sprayed or painted the re-growth.

    As mentioned above, no point in sowing any grass seed till September because it needs cooler and moist condition to germinate and grow.  Have a read of this info - https://www.rhs.org.uk/advice/profile?pid=438 and use the time between now and autumn to make sure your lawn is well prepared - aeration, decompaction, drainage etc. to allow the grass to grow well. 
    Vendée - 20kms from Atlantic coast.
    "The price good men (and women) pay for indifference to public affairs is to be ruled by evil men (and women)."
    Plato
  • Wilson73Wilson73 Posts: 136
    Obelixx said:
    Was the rain before or after the glyphosate?   You need 6 hours of dry, sunny weather for the active ingredients to be absorbed and 2 weeks for it to work and, with a plant like thistles, you may need a second application in case some of the root survives and starts to grow again.

    Personally, I would have cut the thistles down and then sprayed or painted the re-growth.

    As mentioned above, no point in sowing any grass seed till September because it needs cooler and moist condition to germinate and grow.  Have a read of this info - https://www.rhs.org.uk/advice/profile?pid=438 and use the time between now and autumn to make sure your lawn is well prepared - aeration, decompaction, drainage etc. to allow the grass to grow well. 

    Hi it was unfortunate to have had the rain it was only 5 minutes in duration but still enough to upset things,I had painted the glyphosate on with a brush and the stuff that I used was a strong concentration but it may have been a waste of time with the rain.I might look at it again or even leave things until next year.I have a feeling we've had the sunny weather for the year now
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