Turf on hard clay - topsoil or rotovate and sharp sand?

[smashed]

Hi,
In October we gave garden a total overhaul.
Consequently a large slope at the back of the garden has been spread over the whole garden raising it by 40cm or so. Much of this appears to be heavy clay. During the heavy rain the last few months we saw that the water was sitting on the clay (particualrly in the areas where we had been standing when doing the fencing).
We are about to turf the area but I do not want to find that the grass does not take or that it gets waterlogged in heavy rain.

After much research (french drains, sharp sand, manure, rotovating, topsoil etc) we think that we should:
Rotovate
Put topsoil down
Slope the garden slightly to help with drainage.

Is this the best approach (I didnt want to add topsoil or sharp sand originally as this will raise the garden even higher (40cm was high enough) as well as added cost.

Is rotovating a waste of time as the clay will just compact again? Is sharp sand mixed in a better alternative than top soil?

Any advice appreciated

 

[smashed]

Any suggestions please?

 

[Aulus]

I had a similar experience a few years ago, although are you certain it is clay & not silt? I thought mine was clay but being in the Thames flood basin that didn't make sense. Do a jam jar test to be sure.

Definitely didn't want to rotovate, but removed about a foot of what passed for topsoil (45% sand, 50% silt, 5% clay, .001% humus!), then got in 6 tons of new decent topsoil. Walked all over it for a few days, turfed. Still looks a treat. No boggage so far.

I originally tried a french drain, but it was a pig of a job, I gave up!

 

[Thermo]

unless you address the problem of the drainage you will never get a good lawn. A simple network of land drainage is cheap and easy to do with a bit of effort. that will help take the excess water away if its that bad.

you can rotovate the clay, but you really need to add loads of organic material in to help break it up.

a good layer of topsoil on top of that will enable the lawn to take well.

depends how much time effort and money you want to put in. picture may help

 

[smashed]

Hi,
Thanks for the info. I have included 2 pictures.
We rotovated saturday morning as we were running out of time. We found the garden to not be as clay heavy as anticipated. (the heavy clay was mostly in the back corner).
We obviously need to finish removing the big bits on the surface but hopefully somebody can advise as to whether grass will be ok on this? We need to level but dont need it to be the best garden in the world obviously.

 

[Thermo]

its not too far off. rake off all the big stones etc and then give it a covering with a sandy loam levelling soil. that way you can get it nice and flat, before you lay the turf

 

[Jameswren]

My situation is quite similar to this so may as well revive the thread.

I have a gentle sloping garden (around 6m in length) which slopes towards the house. I'm stacking sleepers, at the front, to split the planned lawn with some paving. I'm adding a c100mm section of pea shingle between sleepers and lawn.

I have, today, lifted a load of slabs that were dot and dabbed on a patchy top layer of soil (very sticky and assume clay) with sharp sand mixed in. This is the area I want the lawn.

I've mixed the clay-like stuff, black top soil (found in some beds i ripped out) and the sand then spread it over the whole garden. Not by design but there were 4 of us doing the job so it just happened that way.

I'm after a lush green lawn so what's best to do now? Some things I'm particularly looking for advice on:
*Is the mixed clay, top soil and sand safe to put turf on? Really hoping I don't need to get rid of it having filled a skip today and about 100 bags of soil to the dump over the last few months!
*Is there a specific type of turf to aim for?
*I've read mixing some multi finish over the area may help - is this a good idea?