Help with a lawn which won't grow, 2nd time round!

Hello

I have a lawn which just won't thrive, here's the facts:

- Live on the sea front, it's the rear garden, 18m2, west facing.
- A new promenade was being built 4 years ago and the rubble and soil from existing ground was removed and dumped in a mini car park opposite me – I was doing the garden at the same time so thought it was too good to be true not to pinch the soil and use for my lawn. Did this, filled the area to a depth of 4" and sewed seeds. At first the grass looked amazing, but after a few weeks started getting patchy, very yellow/strawy and eventually areas died back. I tried adding more seed, plenty of water, no luck.
- It got to the point where I called a gardener who (for £140) took a look at it and said they'd add some top soil and fertilizer, more seed and refertilize in a few weeks. They did that and it looked better, but eventually right back to square 1, but buy this time the gardener was uncontactable! Just can't get hold of him, typical!
- Since then, we moved out to restore our home and the grass was left in a bad state, never cut (although only a few areas actually grew long enough to even warrant cutting!), but I thought I'd address it when we moved back in. That time is now and I cut it initially to clean it up and see what it's do, but no change.
- Had a skip this w/e for removing tarmac, and with some space left, I decided to dig up the lawn, and also removed a fair amount of soil (thinking maybe it's contaminated?... although it served a good enough purpose when it was used in its existing location!)
- I've dug down 2-3" and intend to buy some unscreened topsoil and turf it, but I'm worried after a few weeks or months the same thing will happen when the roots bed in?
- I did notice that after heavy rain, puddles appeared – the soil is 4" over shail, could this be a factor? I also noticed dark (almost black soil when digging it up which I think coincided with a pond smell – not sure if this is the soil the gardener added of if it's bad soil? And I also noticed quite a few (every other shovel load) of inch and half long, quite fat, brown caterpillar type creatures but no legs ie. like a large maggot. Have done a search and looks like these guys: http://www.google.co.uk/imgres?hl=e...w=241&start=0&ndsp=34&ved=1t:429,r:5,s:0,i:85​

There were also some crimson red ones were like a cocoon! Looked these up and think it's Bertha Armyworm: http://www.google.co.uk/imgres?hl=e...131&start=0&ndsp=36&ved=1t:429,r:20,s:0,i:137​

That's all the info I can say guys, included all I know with the hope of some guidance/advice. Any ideas???

Thanks​

 

Welcome to Gardeners Corner deansplit.
Interesting problem.Someone will be along soon to give good advice. Nice to have you in the garden,
Jenny namaste

 

Welcome to GC Deansplit.

First may I say, if possible pictures would help with identifying the problem you have.

First of all grass only needs three to four inches of soil to grow in, as that's as far as the roots go down. I too live on the coast here and I'm only 200yds away so have sandy soil.

I'm wondering if the soil you took contained oil from leaking cars or perhaps diesel from the vehicles they were using while working on the promenade. Considering what you've said about the colour and smell it seems likely and there is no way anything is going to grow well if at all, if that's the case.

To be perfectly honest I'd be inclined to get rid of the lot and start afresh with new topsoil and possibly dig down at least 6 inches, if it is oil then it's probably sunk further.
I don't see that the shail should be to much of an issue, but you will have to keep the lawn fed every year as the nutrients in the soil will just leach away.

I'm not sure about the 'grub' problem perhaps somebody else here can help you out with that. Good luck and keep us posted on how it goes.

 

My guess, and it's only a guess is that water isn't draining away and stagnating under your lawn in the shail. That would account for they black soil and smell. Excess water would need to drain away into the sub soil. The roots growing into that water will rot and cause the grass to die, unless anyone has a better theory?

 

1st thing I'd do is 'peek' over the fence and check what your neighbours lawns look like .... if their lawns look ok, then you have a chance of having a decent lawn

2nd thing, is buy a cheap ph kit and do a basic test to check the ph level

 

Definitely no oil in the soil - it was from the plant areas in front of a leisure centre some 20' from the road.

Re: drainage: Mmm, I did think this too, but surely, in dry spells, would it not have cured itself/attempted to grow, then dies back as soon as the rain builds up again? We 'are' in Northern Ireland, so do get a fair share of rain, but also good dry spells too...

So the grub problem not a worry? Are grubs evident in all/most lawns? Of course, unless you're a gardener, you'd never be aware of what lies beneath, so I immediately thought it was out of character to have them...?

 

Yes, next door is fine, lush in fact! But the soil from mine is from 1/2 a mile away...?

Is there any pH kits you can recommend? I have the tester strips for my tropical fish tank, but they're no good1

 

Taking grubs out of the equation, if I re-topsoil the top 2" and turf, and it was the soil which was contaminated, would the lawn still be ok? I mean, with 2" of good new soil, would it dilute the bad soil or as soon as the roots grow beyond 2" would the grass die?

 

Hi dean, If water is puddling on your lawn it isn't draining away. I would have thought soil on top of shail would be ideal for drainage. What is beneath the shail? how deep is it?

 

Hi Robajobs, er short answer, no a clue! the beautiful Victorian treelined garden was flattened and tarmaced when it became a rotten B&B, so the shail was the base for the tarmac, but like you, I'd have thought the shail would let the water drain.

I can tell you we're at the foot of the Mourne Mountains (behind us), but only a road between us and the sea wall in front. We had to have pile foundations for a recent kitchen extension we did (15m from the effected soil/grass area - from back of house towards the area) and had to have a rock breaker in to make way for a garage we built some 15m the other side of the area (ie. further away from the house - basically the foot of mountains, so I know it's granite galore below at the furthest point, but very soft between that and the house ie. until we hit granite for the piles). Quite clayey as far as I can remember when they piled, would that cause bad drainage?

 

It may be that the soil that you have is in fact peat based, and acidic.
As said above, check the PH level and go from there. If it is acidic, you will need to add lime to it to encourage growth.

 

Thanks Eddie, if I introduce good new soil, and then mix it up, will this dilute the acidity to enable good growth or do I have to get the existing soil good first? I could do without removing anymore soil, for labour reasons, and would need to hire another skip! :(

 

Hi Dean, you said the grass grew well on the original soil you pinched then died back, but it was fine where it was on the prom. Then the 'gardener' put top soil and fetiliser on top of that with the same result. If the soil wasn't suitable I doubt the grass would have grown much at all, from your last post I still think it's drainage and the problem is below the 4" of topsoil. As suggested you can buy some bags of lime it can only help.