RENEWING AN UNEVEN WEED INFESTED LAWN? HELP

Hi, myself and my girlfriedennd purchased a house 6 months ago which is about 10 years old (new build).. when they laid the turf originally they obviously didn't pack it down due to it now being extremely uneven (it can drop between 6 and 9 inches in some spots. also there is a plethora of big,thick stubborn weeds (one of which i tried to dig out, and after getting down a foot and it still being 2" thick i gave up )

we are now at the stage (financially and emotionally lol) to begin work to attain a nice flat weedless lawn.
what we want sounds simple (it probably isn't) but i am a complete novice in the garden and would love some advice:

basically how do we rid ourselves of these ridiculous weeds, can i buy some acid strength killer without killing off the future fertility of the soil?
and whats the best way to level the ground? my dad could have access to a mini digger, and i was thinking scooping out a good 6" and going at some of the weeds, getting rid of that and then throwing a bit of top soil down, putting a roller on it, giving it a rake then laying some new grass??

please bear in mind that im thinking of attaking all this in April, i don't know if that makes a difference?

sorry for the long post, and thanks for the advice in advance, because anything will be a help! cheers. Jamie

 

Depends if the soil below the lawn is full of builders rubble (sadly, often the case) or not.

If it is then it needs a complete sort out - it will need digging over to remove all the rubble and open up the soil to improve the drainage. If not its probably just settled over time because it wasn't properly compacted initially.

You don't want to go throwing away the top bit and buying lots of replacement top soil in, but it does depend a bit how bad the weeds are and how much, or little?, grass you have.

You can level a lawn in two ways:

1. dig H-shaped slits in the lawn where there are bumps, or hollow. Peel the turf back, add soil to fill in the hollows, or remove soil to remove the humps, and roll the turf back.

2. Cover the lot in soil, level off, and over-seed. If you are doing this you should first mow the lawn to within a whisker of its life, and then over-seed (about 50% of the normal amount of seed compared to sowing a new lawn, as the old grass will come through too). You are not looking to put a lot of soil down, just enough to fill in the hollows. You may have to repeat this in a years time to get it really level.

You could spray the existing lawn with Roundup / Glyphosate weedkiller and then start over - but that is a lot more effort than repairing a lawn, so before you do that you need to decide that it is so bad there is nothing to salvage. Wait for warm weather before using the weedkiller because it only works well if the weeds are growing strongly. You need to then prepare a proper seedbed - rotavate the whole lot, level off carefully, make a seed bed, sow the grass (or lay turf), and then nurture it for the first year. If you sow in April the grass seed will be growing at the same time as the weeds, and it will need watering regularly right through the first summer, and you won't be able to use the lawn to walk on for a couple of months. If you lay turf instead that will be reduced to about a month, until the turf roots have established into the soil, but it will still need watering all through the first summer (but you won;t have to worry about weed seed growing too!)

Either way, you can kill the weeds in a lawn using a Selective Weedkiller. That will kill the weeds, but not the grass. You can get a granular type which includes fertilizer - so you just put that on like fertilizer but it also kills the weeds, or you can get a concentrate that you mix and apply with sprayer or watering can (it works best if you have put down fertilizer a few weeks earlier so the weeds are growing strongly).

 

Thanks for posting!
ok, so ill be unable to kill of the weeds with Roundup in time for my planned april start due to the cold weather?
could you tell me the pros and cons if i went about it this way:

get a rotavator or mini digger and churn up the top 6-9 inches of the soil, grass and weeds, pick out any of the weeds that come up and dispose of them, then re use the rest of the churned up soil and spread it out evenly throughout my garden, next i would get a roller on it to proper flatten the ground, and then throw an inch of topsoil on and rake out evenly again. Lay grass and water, spraying any specific weeds that grow with roundup.

Currently the grass is patchy on my lawn, with about 25% tough weeds mixed in... ive read somewhere that laying soil with sharpsand mixed in can help.. is this true?
thanks again

 

I think you can Roundup ready for April. The grass/weeds should be growing fast enough by then - but you need to allow 2 weeks for it to be killed off, so spray 2 weeks before you want to rotavate (and spray on a dry day - you have to have 6? or 8? maybe? hours of dry after application).

Leave it as late as you can to fit in with your rotavating.

But .. .are you sure it is really that bad? Its a lot of work, cost, and time during which you have "no usable lawn" if you start from scratch. 25% weeds sounds "repariable" to me - provided that the soil is OK and not full of bricks and a decent depth - rather than just a couple of inches.

I wouldn't use a mini digger as that will compress the soil, rotavate and then level by hand (get a ladder, attach a rope, put a few blocks on the ladder to weigh it down a bit, drag it North-South and East-West to level the surface.

You can walk over the lawn to make the seedbed, rather than using a roller. Place first foot on ground, then place other foot next to it with the heel in the curve of the ball of your other foot - so you progress half-a-foot at a time. Roller is likely to "span" the soft bits and not compress them as evenly.

Then drag the ladder over the surface again to smooth out any bumps & hollows.

I don't think you need topsoil unless you soil is really bad, but if you do then you need more than an inch or two. The surface needs to be worked well for 6" to 9" depth. Grass won't grow in just an inch or two (although that might be your problem currently?)

Yes, sharp sand will help if your soil is clay.

If you have a decent depth of soil, but it has got badly compacted, then you need to aerate it. If you have a lot of moss in your lawn then it is probably compacted. You can stick a fork in, wiggle a bit, then repeat. You need to make a LOT of holes! quite close together.

 

Hi Jamie .
Kristen has covered all the major points in his replies ..and I would agree not to use a mini digger ..
Make a few test holes to check what the ground is like . check if it rubble or if it is very compacted this would then help to decide the best way forward .
Dave

 

The main point is to not give up or lose hope. When I moved into my house the lawn was in a poor state. Over five hundred weeds (yes, I counted!) and just hopeless. The worst I had ever seen. But what it needed was hardcore TLC. So it was a serious amount of weedkiller. I used Verdone and it took several weeks and applications almost every other night to get rid of them. Then it was scarify, aerate, and feed. Lawns are tough and this reminded me that any lawn CAN recover. I hope that helps.

 

What weeds are we talking about? I bet they're Dock (large leaves, very deep, thick tap root)?

That being the case, I think there's very little point trying to dig them out. You won't get all the roots out and they'll just come back.

Assuming there is still a lot of grass, and that grass is still healthy, I think I'd just try to repair the existing lawn.

You can spot treat the Dock leaves (or any other weeds) as they appear. A trick I learnt is to cut the bottom off a 2 litre pop bottle, and remove the lid. You can then slot the pop bottle over the target, stick the nozzle of your RoundUp sprayer in the lid, and spray. The bottle will then container the RoundUp around the weed, and stop it drifting to the grass.

Being fundamentally quite lazy, if these dips you speak of are only small, I'd just fill them with a mix of sharp sand and compost, then overseed that bit.

Regular mowing will also get rid of the weeds eventually, because you keep topping them before they've had chance to get any energy from the sunshine (ie you stop them from photosynthesising), and then eventually they run out the energy reserves in their roots, and starve to death. Regular mowing also prevents the existing weeds from setting seeds, and prevents any weed seedlings from getting a chance to establish.