can I use sharp sand to open up the clay soil of my lawn

Hi Stockhyrst, welcome to GOY.
You need to spike your lawn with a spiked roller, we can hire them on this side of the pond. Then brush in a mixture of sharp sand and good top soil.

Using a fork works weel, push in to about 4inch and wiggly, pull out, sprinkly over sand (make sure it washed sand as normal sand contains salts hat do more harm than good) and brush in with a stiff broom. Repeat untill holes are filled. Your lawn will look in a terrible mess when finished, but will recover quickly

may I tell you a little about clay, we regard it as thick guey stuff, but we are wrong infact clay is verry fine, finer than the sharp sand you want to brake it up with, what you should be doing is binding it togather,I use peat or leafmold, to turn it from fine flower to granulated sugger so to speak, may be hard to belive, but it is true.

I am confused now - just when I thought I would try sharp sand on my front lawn!
my clay is like concrete nothing guey about it so how could I treat a lawn with leaf mould? it would do what?

I would go for mixing both perhaps! WASHED sharp or horticuktral sand is best. Best of both worlds and advice i know, leaf mould and sand, who knows the true answer..... both right!

To anyone taking on this treatment of a lawn on heavy compact clay, you need to aeriate the top with holes, (spike roller). Some rollers have hollow tines which leave small pieces on top of your lawn. If you brush these back in with sand and soil the holes will stay open for some time, letting in moisture and together with feed and weed you will get a good revived lawn.

In the old days when we had winters,
the lawn did not grow in the winter, so for at least three monthe we did not have to cut it, so what we did if we had your problem was cover it in farmyard' and let the rain and frost get on with doing the job for us. you should spike your lawn on a reglour basis even a decent lawn, I surjest a good forking
and a dresing of fine peat or somthing like it. and keep doing it until you have a lawn like chester zoo ,I belive it only took a hundred years to get it like that.
just joking ,the best of luck,

just a note I was in a garden center this afternoon, and I spoted some spike rollers , they looked rather light and I realy do not think they would do the job, they were £23.00 but also there for£9.99 were strap on spike sandles for going under your boots, now they would do the job. the spikes were the same lenth but with your weight they would go in 2to3inches.

Aslong as you dont stand on your own foot with them. Only trouble is surely too much coil or peat (not PC!) would esncaouarge weeds?
Best is fork i find as its an open hole and therefore more sand can get in.

I think we all have our own ways or sand/compost mixes!

you could have a point there nick08 after all stockhyrst is daft enough to listen to us two,
he said his clay was like concrete, weeds are the only thing I know that will grow through concrete, if he dose a good job with the sandles just think what wonderfull leg musels he will get, I would not like to face him taking a penalty, by the way, nettles are grate at braking up clay the soil from a nettle bed would be better than sand,

Use hollow tine fork approx 2inches apart all over, clear off the waste which comes out,apply sharp sand mixed 50/50 with topsoil brushed in with stiff brush.

And then spend a few days recovering as muscles will be used you never knew you had!