raised beds in soaked clay

Hi, I am about to start some raised beds for veg in a turfed garden. I am adding top soil + compost to a height of about 25cm. could do more if required.
Should I removed the turf? can I put grass cutting at the bottom? should i dig the clay a bit ( ? add some sand) even though I aim to grow things above?
should I put wet cardboard down under the topsoil as suggested in another site?

in other part of the garden I have started to dig and add sand + compost for flower beds but the soil is heavy water logged clay with addedd building rubble so raised beds are my only hope for veg this year.
thank you for any advice.

 

Either spray off with round up and break up the dead turf or lift the turves turning them over before adding your topsoil.

I wouldnt add grass cuting as youll get weeds, compost them.

In my mind wet card is weeing in the wind and a waste of time, turning the turves or spraying and forking is the best option.

If youll be growing root crops then best to break up the soil below, completly stripping and removing the turf alltogether (if you stack it turned upside down in a corner it will break down)

 

Hi Veg-n Roses, welcome to the forum. When I cleared my garden patch for veg I took the lift the turf and stack option so I ended up with a lot of good loam. If the clay is that bad and waterlogged I think I would dig some of that out as well. Breaking it up is easy with a pick and mix loads of leaves and farmyard manure in the hole.I did this in my last garden that had heavy clay and transformed it within a couple of seasons to quite a workable soil. Mix your clay with soil and plant your roses in it. (I'll probably incur the wrath of the rose growers for saying that.)

 

Hi Veg-n Roses and welcome. Clay is a subject that keeps coming up. What you do depends on how serious you are about improving your clay. I started a thread on this some time ago. http://www.gardenerscorner.co.uk/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=20;t=000134;p=1#000000

Last Autumn I decided to do redo my front garden, which the thread shows. I had previously done the same to the back garden, which was also solid wet clay. The treatment has improved the soil enormously and is well worth doing. The key elements are added sand and gravel and lots and lots of organic material. Work out what you need then treble it. Don't worry too much about mixing everything perfectly - the worms will do that for you.

 

thanks everyone.
I admire the work you've done PeterS! too large a scale for me to contemplate in one go but I will work it one bed at a time.
Terrier I have done just that with my roses (LAST SEPTEMBER) when I moved in and they seem to do well so far so cross fingers...

and I won't bother with the cardboard instead Ill set a corner of the garden for the upturn turf.

when I dig the clay I sometimes get some blue or yellow clay. is it natural or is it polluted from the building work that was there before (this is a new estate)?

 

Its natural, probably marl. If you were to dig down 1 metre and look at the profile youd see it changes coulor/ textutre as you get deeper until you hit rock.

 

When making my beds i removed the turf, dug over the soil to a spades depth, then added topsoil and compost.

I did make these in the autum not the spring so im not to sure if that has any affect on growing in them this year.