ᐅ How to Prepare the Soil Before Laying Sod to Keep It Weed-Free?

Hello everyone,

After completing our new build, quite a bit of weeds have appeared in the garden. On Friday, we are getting 20cm (8 inches) of fresh topsoil, and then we plan to finally sow grass seed. We have cleared the plot of all tall-growing plants. However, I recently found out that the flat, widespread weed remaining is couch grass (quackgrass), which I hadn’t looked into before, especially how difficult it is to get rid of. It’s practically everywhere on the property. Unfortunately, we won’t be able to remove it all by hand.

At the same time, I’m worried that the couch grass will penetrate the 20cm (8 inches) of topsoil and sprout through the newly established lawn.

How would you proceed? We do not want to use herbicides. Is it enough to properly fertilize and mow the lawn regularly, and will the couch grass eventually be suppressed or weakened by constant mowing? Or will I have to remove the couch grass with a weed puller from the lawn repeatedly until it no longer returns? Or am I worrying too much and the couch grass won’t be able to grow through the 20cm (8 inches) of topsoil?

Also, does it make sense to use a rototiller with the fresh topsoil, or not really?

Maybe you have some good advice.

Thank you very much
Herr Stein

I would just relax. Will the couch grass come through? No idea, but probably not. It doesn’t really matter anyway.
It came from somewhere and it will do so again 😉 Just like all weeds.

You won’t be able to keep it completely weed-free. If you want the lawn to grow, the weeds will grow too. In our case, a lot of gooseweed appeared very quickly and grew taller than the grass blades. As soon as I could walk on the new lawn, I pulled out each plant individually. Then I mowed it for the first time quite soon. There will always be some other green things mixed in.

Thank you for the reassuring answers. I never wanted to be the kind of person who pulls out every little daisy. It was just the idea that the weeds would take hold in the garden faster than the lawn that I found a bit unsettling...

Hello
We also had a lot of couch grass after the lawn was seeded. This was despite the entire topsoil layer, along with all vegetation, being replaced with at least 10 cm (4 inches) of cultivated substrate soil.
Since couch grass spreads through its roots, we carefully removed it by hand. Any individual plants that regrow are removed immediately...

That must have been quite a lot of work ...