clay soil under lawn

wayne99

Hi all,

Iam after some advice if possible,

We currently rent a property from a housing association, it is a new build (2 years old now).

Now the area I live in is made up mainly of clay, now our back garden has really dense clay soil.

In the summer the ground dry's out so much on the surface it cracks, and the grass dies.

In the winter the soil is not permeable enough to absorb water and the garden fills up like a pond, and guess what ..... the grass dies.

Now in the next 6 weeks i plan on trying to sort this issue out, or make it somewhat better.
I have been told that I should try and improve the soil base under the grass (obvious) now i have been told to dig down at least 200mm and replace that soil with graded top soil and sharp sand mix it in with the clay below until the mix is even (not to much of each - clay, topsoil and sharp sand) and this apparently will sort the issue.

what do you think ? does anyone have any other tips or ideas of how to improve the soil ?

Where i live unless I have it craned in i cannot get a mini digger into the garden so i cant do a deep dig out.

also when this is done and I need to get the lawn sorted, what sort of grass should i be using ? the garden is east facing so doesn't get allot of sun, and there are a good few shaded areas, what would you recommend ? seed or turf ? what sort ?

some advice would be fantastic
thanks in advance

wayne

nodwah

When you're in a new build, in my experience the soil you get is the churned up sub-soil that they've dug out to make the foundations. I expect it will be full of broken bricks, bits of pipe and all the other random off-cuts from the build.

I would say, get rid of as much as you can and do what you've been told - and spike all over and back fill with sharp sand.

As for the shady areas, IMHO you're on a loser if you want good grass. My front garden gets no sun for 3/4 of the year and so the grass was a patch of weeds and moss - i dug out the worst and put stones in instead. What about shade loving plants?

wayne99

Thanks nodwah,

were up for putting plants in, the main consideration is that we have a 7 year old boy, and the garden is small approx 10mtrs long x 5 mtrs wide, we have a decking area at the top of the garden joining the house that is approx 2.5 long x 5mtrs wide, so we have 7.5 mtrs of grass.

The garden is sloped to the bottom (which is a nightmare when it rains as all the water goes to one place at the bottom and creates a pond on the surface that in heavy rain fills up at least two inches and takes a day or so to drain away) but when i sort the soil out which should sort the drainage issue out iam going to put a retainer in and section the garden into 2, so we can have two flat areas of garden.

last gear I built two planters one small around 40cm long x 25cm wide and one large around 1.5mtrs x 30 wide and we have been using those as the ground is so wet we didn't want to plant anything in it for fear of it dying just like the grass.
What plants would you suggest ?

Wookey

One problem will be that even after taking out the top 8" of clay and adding soil you are still left with clay below, with heavy rainfall you will still be likely to get a flooded garden. If possible try to create a run of when re doing it with a slight slope towards one corner, in this corner you would ideally like to have a hedge or a few trees as these should have a far deeper and better soil system around them there by aiding drainage. If your grass had been dug over and forked thru a few times before the heavy cold weather the frost would have helped break the clay down quite a bit. If there are no worms present currently in the grass look to add some as these will help a lot.

wayne99

i have done a small dig in one area and there were plenty of worms, which is a good sign.

The clay seems to get quick bad after say 8 - 10 inches deep, a friend of mine suggested digging down at least a meter and adding stones and all sorts of other things to it to aid the drainage but going down 1 mtr in thick clay without the aid of a digger will kill me lol and I just don't think its a possible.

i would make a slight slope to one end and then possibly add some kind of surface drainage to that area but my worry is that even if I add surface drainage it will just fill up with water and not free drain into the soil below, flipping clay....

Kazipoo

Try adding some grit to your mix. our front garden is very clay based, yet our plants and grass thrive (despite getting water-logged from time to time), because we regularly aerate and reseed the lawn, and when we plant we add soil improver, grit and bonemeal, it has worked so far for us, and, when you consider that our old neighbour told us that nothing would grow in our front garden, it makes it twice as pleasing!

Perhaps you could try being a little artistic with your grass and create sections or shapes where the grass would benefit from the sun?

There are lots of shade loving plants, I have an area that never sees sun all year and even grow aqueligia (sp), gypsophelia and fuchsia's, as well as hosta's, fatsia japonica, astillbe (sp). It really depends on what type of garden you would prefer.

doshunta

Well you aren't alone!

I dropped our garden 3-4feet 12m *8m last year..it took 155 tonnes and a lot of hard graft, only to find that it pooled just like yours...only on our new patio!:mad:

Thankfully I waited to see if this would happen before adding the finishing (expensive, decorative) layer, which I'm doing in April.

To try to fix the problem I've just done two things:

1. Flattened the slope towards the patio
2. Dug a 2ft deep trench with a slight slope away from this patio - to an area where I have dug down to 3-4 foot. I will fill this with rubble and sand to soak up as much runway water, as I will the trench

I am then going to build up 3-4 inches of hardcore across the whole garden, adding a sand layer too, then I will add either topsoil and tuf or gravel (as my new design dictates) to each area.

This will build up the height slightly, around 5-6 inches, and to save cost I'm going to use railway sleepers for my retaining wall (as I have round the garden borders).

I hope this is helpful...

oh!, and wish me luck! :rotfl::rotfl::rotfl:

The idea is to create a greater absorbtion layer in the garden.

doshunta

..and by the way, don't even think of digging clay unless it is a day or two after rain... it needs to be 'not too soft (claggy and gluelike)' and 'not too hard', as such extremes are impossible to work with without a digger.

And please realise how much soil you will produce digging out the area you have there... it can be expensive to shift if you don't have a mate who is a farmer with a tractor and trailer! (155T takes c 13 lorries & c £2000-£2600!)

bottlehalffull

Build up with horse manure (well rotted) and top soil? But you'd probably need to break through the clay pan in places so drainage is improved.

You might be best putting a french drain type thing in - very deep hole filled with stones...
Tricky and potentially messy.

Oo ... what about worth with it and have a bog garden at the bottom? You can buy some really interesting plants ...

starstella

bottlehalffull wrote: »

Build up with horse manure (well rotted) and top soil? But you'd probably need to break through the clay pan in places so drainage is improved.

You might be best putting a french drain type thing in - very deep hole filled with stones...
Tricky and potentially messy.

Oo ... what about worth with it and have a bog garden at the bottom? You can buy some really interesting plants ...

I agree with bottlehalffull.Work with it and save your self a lot of hassle.My garden is clay based we have been here 10 years and I have added loads of compost over those years.When I plant things I make sure I put lots of grit and compost and mix it in with the clay.Everything I have planted has thrived.Clay is very nutrious and plants seem to love it.For my lawn I bought 2 tons of topsoil and then turfed it.Well (what I really mean is)
someone else did the hard work.:rotfl:The turf has taken but the preparation was poor and I now have lumps and bumps to sort out( any advice on that would be welcome)..Good luck with yours and a bog garden can look great:)

Sarah_28

Well it appears i am not the only one with a water logged garden!

We moved here a year and a half ago and have a 120' garden. It's on a slight slope running downhill towards our house.

The garden is made up of clay soil and gets waterlogged all the time except for summer, our next door neighbour has the same problem (he's just bought the house to do up and sell on)

so for spring, autumn and winter you can't go out without your wellies on. We have two children as well so it's a nightmare for them to play out except in summer. In winter the large puddles in the grass turn to big lumps of ice!

Ive heard about soak aways, digging a big pit and filling with rubble, also the drainage systems whereby you lay piping under the ground, the problem is that the garden is 120' long and about 5m wide and both of these drainage options sound like hard work and lots of money!

Any ideas which method would be best? If we leveled the garden it would probably have to be on 3 different levels, getting higher as you went up the garden,

Also has anyone got a similar problem with a large garden? if so how much did it cost?

My husband and I both work full time and with 2 children I think we simply would not have time to get such a large job done, although we are not afraid of getting our hands dirty.

The area is also known for subsidence, not sure if this is something that will effect the lawn?!

Thank you in advance for any info.

Happy Lawning...