Raised beds over grass

[Spunky]

I'm building a 4" raised bed do I need to dig the grass over or can I lay it directly on top?

[teakdesk]

Do you mean 4" high or 4' wide?

4" high is not very high so I'd definitely dig over the lawn underneath.

If you are making it, say, 8" high then you could perhaps get away with just loosening the grass.

If you want to raise root crops then I'd dig the lawn whatever the height of the beds!

[Spunky]

4" high teak desk thanks I'll dig the grass out and turn it over

[teakdesk]

If you remove the turves and stack them upside down on top of each other you'll have lovely potting compost next year!

[Kristen]

I would definitely dig underneath a raised bed thoroughly, it will add drainage and root penetration. But you only need to do it just the once, thereafter provided you never walk on the raised bed (which will compact it) you can do without.

You can start with a no-dig method (such as the lasagne method) , but personally, on heavy clay, and in particular if it is compacted and/or has a pan, I think that an initial digging gets it up to full speed more quickly.

[Two_Sheds]

If digging is too difficult, then consider just forking over the area and perhaps drizzling some sand into the fork holes to aid drainage

[Spunky]

Thanks all I ended up treating it all with round up last week and dug it over today added manure, homemade compost and spent compost, bring on spring!

[Two_Sheds]

A week isn't really long enough for the Round Up to do its job

You might as well just have turned it over, without using the RU

[Spunky]

Yep you're right I couldn't be ar?!d waiting tbh so just dug it over anyway lol