Struggling beginner

Hi and thanks for taking the time to read my post.

So, we have a smallish garden (about 45 square metres) in a newish house. The garden has had poor drainage since we moved in and has got worse to the point that there isn't much grass left and it's more like a mud bath. My plan is to dig up the garden, slab some of it (about 7.3 square metres), put down artificial grass (20 square metres) and then just gravel/soil borders for the rest. I've looked at various guides online and watched YouTube videos and think I have the general gist of it. I'm just not sure if this is a bit too big of a job for someone with very little experience. Also I'm getting varying information with regards to how much and what to put under the artificial grass and slabs.

Any help would be greatly appreciated

 

Hi and Welcome to the Forum,

It sounds like a sorry state if the garden is so muddy this time of year.

Might be best if you can find the reason for so much retained water and a way to drain it away before trying to put down any new surfaces, which are likely to short lived because of the water beneath.

A picture of your garden and surroundings might help us see whats causing the problem and offer some ways to improve things.

Do you know if your roof drain pipes fall into the main drains or go into a soakaway in your garden which seems to be more common these days, you can often tell by looking in the iron works/manhole covers and seeing which direction they flow.

 

Thank you for your response.

This is what the surface goes like, the dog makes it worse and treads the mud in the house etc. The estate we're on is terrible and a lot of people have had the same problem and ended up digging and replacing. I was thinking of digging down far enough to put type 1 down for drainage. The drain pipes are separate and go into the main drain, it's just really bad soil as far as I'm aware.

 

Some places have had torrential downpours recently are you one of those places, or would you say you have just had normal rainfall for the time of year.

 

It's not excessive right now, but it's always been like it. Over the years it's got worse as the grass had died. We've tried forking the ground and putting grass seeds down but it hasn't helped.

 

The way its puddling and its colour looks like the soil has a lot of clay in it.
Expect if you scoop some up it will be like Plasticine.

If you lay anything like paving onto clayish soil like that, what you can find, as we did when we put down some block paving only with a too shallow sub bed, is that when the clay gets wet and you walk on it, you can feel the whole surface moving, quiet an unreal sensation.

Expect the clay will go down quiet a bit, though doing a couple of test holes, say down to 40-60+ cm , will tell you what is down there.
A soak away is a common drainage method, but if its surrounded by clay then its just not going to be able to escape.
Drainage - Soakaways

How much to dig out and replace with hardcore, gravel or good soil is hard to say, but you do need to try and channel the water away otherwise the surrounding clay might just hold the water in your dug out area and make things worse.

Does you garden slope that allows you to drain the water that way and escape ?

 

Yes I think it is like clay, awful stuff.
The garden is relatively flat, which is why I think it's worse as it just sits there.
I'd read about putting 35-50mm of hardcore under the lawn and 100-150mm under the patio. Not sure if I'd need any under the borders?
I'm guessing I need to dig down to see how far the clay goes first though?

 

Are you surrounded by other gardens, who probably have the same problem?

I have clay, and clay is the subsoil, I don't think there is really a feasible chance of digging down below it, but over the years by adding other stuff such as compost, sand etc. to break the clay down it rarely gets that bad even in the worst rains, but I am on a gentle slope.

I think if the water has nowhere to go whatever you do just creates a sump for the other gardens in the area.

 

Some developers scrape off the top soil when levelling the site, this then gets sold off as top soil. Leaving gardens composed of subsoil which then get turfed.

 

If possible, might be some merit in raising the level of the garden with new soil and paving rather than digging stuff out, but do ensure it does not breach the 150mm / damp proof course of the house wall.

 

Looking at your image the problem is clayey soil, to solve this you need to be adding an organic humus soil conditioner plus horticultural girt, or concreting sand, this helps to break it down.

When your soil is clayey, most people think by forking and adding some sand will cure the problem are wrong, it can have the opposite effect. Clay and sand is like creating a material akin to concrete, you would need to be adding at least 40-50% sand to break down very clayey soil, less than that and your likely to increase it being waterlogged.