Clay soil in a new build and hard aggregate below the clay

Hello all, I'm just new here.

I have moved in to a new build house with very damp clay in the garden. I thought this was my main problem so had been looking at getting well rotted horse manure to help break down the clay.

It now seems that in my flowerbeds, some areas (near the path put in by the developers) there is only a shallow layer of clay and what seems like a layer of hardcore aggergate. It's very difficult to clear with a spade alone and feels like it is going to need a fork/pick. Is this a common problem in new build gardens? I know that the site had significant groundwork and earthmoving done before the foundations were placed.

I presume I am going to need to "double dig" to be able to clear enough of this hardcore away but is this actually going to need a digger to do the excavation?

I also presume that the hardcore is going to be exacerbating the already waterlogged clay?

When I do eventually clear the hardcore, how quickly can I expect the horse manure to help give me more workable soil?

Thanks

 

Welcome to the forum! @deejonny I also have an abundance of clay and I finally gave up on trying to dig out and enrich beds so decided to do raised beds.

I'm sure others will join in the a.m. to offer other ideas

 

Yes it's commom (cheap way of getting rid off ) unless it's been a brown field site before hand

 

Welcome @deejonny. Sadly yes. Totally normal for builders. It saves them getting more skips. And also, even if they have chucked a lot of rubbish away properly, they frequently just drop bricks, tiles, spare cement from mixer wherever they are. I had my garden terraced and they were finding HUGE lumps of concrete (though the people doing the terracing also left their own debris!). Builders do not (in general) consider the garden.
I would suggest you trial dig an area - somewhere fairly close to the house where you reckon they might have flung most waste. If you can clear it down to subsoil with a spade and pickaxe, then you might not need a minidigger. It will also tell you if they have put enough topsoil back or if (again frequently) they have lost most of it and just imported a dusting to hide the subsoil.

 

I'd second this. Builders are lazy sods. If there's a cheap, quick, slipshod way of doing a job, they will always take it. The only way to get them to do a job properly is for you to be the one hiring them, and for you personally to be on site every second and watching what they do.

I'm sure there are builders out there who aren't like that. The evidence is against it though.

Back to your garden, the problem is likely to be more than just the flowerbeds. Chances are that your lawn is going to have major drainage problems too, and that will be an ongoing problem for the whole garden. Does water tend to form puddles on the lawn when it rains, and do those puddles soak away or stay there?

 

Thanks for the all the input. I really appreciate the help.


I’ve taken the pragmatic decision to have artificial grass as it’s a north facing garden in the west of Scotland so it was always going to be wet.

I’ve added a few pics. The problem area is really the large bed at the back. The really compacted hard gravel seems to be worst closer to the back path. It looks like that is where I am going to have dig that out.

Does the rest of the ground in the 3rd picture look ok or does the gravel at the bottom of that picture also need dug out?

4th picture just to show how claggy and sticky my clay is!!

Thanks again!

 

It looks like that's going to be a sod. A rotavator will loosen things up to help you with the double-digging, but it's still going to be hard work. My first garden was worse than that though - take your soil and then let it fester for 20 years, basically - and double-digging plus plenty of mulching every year turned that around. So don't abandon hope. But also don't book your gym membership yet, because you have a lot of exercise with a shovel coming your way.

I wouldn't do anything just yet though. While the soil is still waterlogged, anything you do will make things worse. (It's probably covered with snow right now anyway!)