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Pond edging

DesthemoanerDesthemoaner FlintshirePosts: 182

Hi all

Quick question about pond edging.

  I've just begun relocating an existing pond because it developed a puncture which I think was caused by a root. I suppose I could have tried to repair it, but I never really liked the siting of that pond anyhow, so decided to take the chance to make something better.

The most appropriate alternative site is adjacent to a sloping part of our lawned garden.This sloping lawn forms one edge of the new pond, the other sides being a patio laid with flagstones. My intention is to lay stone edging around the three flat sides of the pond, mortared in on top of the liner and existing flagstones, and then lift the turf on the slope, push the liner underneath and re-lay the grass.

Question is, would placing liner underneath the turf be likely to interfere with the growth of the grass in any way? I anticipate placing perhaps a foot of liner in total underneath the turf. 



  • DesthemoanerDesthemoaner FlintshirePosts: 182

    Can't seem to post pics of the situation, unfortunately. Dang and blarst. 

    Last edited: 04 July 2017 18:28:15

  • YviestevieYviestevie Kingswinford, West MidlandsPosts: 6,894

    Can't see how you can turf over pond liner. The liner is waterproof so there would be no drainage. Anyone done this?

    Hi from Kingswinford in the West Midlands
  • DesthemoanerDesthemoaner FlintshirePosts: 182

     Having thought about it, I could put the turf over the liner then prick through the turf with a fork to make that part of the liner permeable. I would probably need to anchor the liner beneath the turf anyhow, what with it being on a slope. 

    The water level is never going to be high enough for the pricked part of the liner to be a problem, because there'll be an overflow drain at a lower point on the opposite side of the pond. 

    Having said all that, I am starting to get the feeling of having made a rod for my own back by siting the pond where it is. Just couldn't find any alternative site that ticked all the boxes. 

    Last edited: 04 July 2017 19:53:21

  • DesthemoanerDesthemoaner FlintshirePosts: 182

    Well, I've done a bit of retrospective research, which is probably never a good idea. 

    Seems that having grass as pond edging can cause problems; some of them pretty darned obvious.

    Drainage of muddy water from the turf into the pond,  especially given my situation with a slope. The possibility of lawn treatment chemicals getting into the water when applied to the surrounding area. The grass can grow into the water, as can the roots, so that would need to be dealt with. 

    Thinking on, I reckon my best bet is to bury some thin concrete slabs on their ends against the edge of the turf and drape the liner over those. It'll mean that more of the liner would be visible than I would have liked, but hey flipping ho. 

    Edit: better still, cut a slit, tuck the edge of the liner into that then bury the concrete slabs on top of the liner against the edge of the turf. Starting to get a picture of it now. 

    Last edited: 04 July 2017 20:11:35

  • After the problems we have had with concrete and cement in our new pond I would do anything to avoid experiencing these problems again.  From what we have been told by various "pond" people it would appear that using either of these materials anywhere near a pond leach lime into the water and  will raise the PH levels of the water enough to kill some of the pond plants.

    We have just drained our water from the pond for a third time and still the PH is too high. Sorry if this advice spoils your plans desthemoaner, but I wish someone had mentioned this problem to us before we went ahead with using cement in our pond.

  • DesthemoanerDesthemoaner FlintshirePosts: 182

    Thanks to you both for all that.

    I've constructed numerous small ponds over the last few years, always finishing the edging with flags or broken pieces of flags, and mortaring them on top of the liner to keep it in place and give a neat finish. There was one occasion when I dropped some cement in the water and yes, I drained and refilled the pond to be on the safe side. Other than that, using mortar has never given me any obvious problems.

    Having not gone for the concrete collar solution, Doghouse (because I'd never heard of it till I saw your post, to be honest) my intention is to cut 450mmx450mm flagstones in half and place them round the pond on the edges where the liner lays on the patio, and then find a way of finishing off against the fourth side where there's a sloping grass bank. I've got a couple of ideas, including wrapping the liner over a 6x1 plank and securing that against the bank by digging the ends into the surrounding turf (though obviously wood will rot in time) or again as above, using coping stones.

    Today is going to feature some experimentation, and probably a bit of swearing too. image

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  • DesthemoanerDesthemoaner FlintshirePosts: 182

    Thanks for those, Doghouse. Brilliant stuff, looks just the job. Mine is an altogether more modest affair, but I'm still determined to get it right.

    In the end I went for not cutting the flags but laying them whole, as I was worried about cement dust created by the "whizzer" getting into the water, the pond already having been filled. So at present I have 450mm square flags laying on a thin bed of sand around 3 edges of the pond, and I'll probably leave things as they are without using mortar because they seem pretty solid. Its just that fourth side, which I have finished off as above with a plank and the liner folded over it. However, this has left a lot more liner exposed to sunlight than I would have liked, so I intend to look at that situation again. 

    Chrissie, if the section of lawn abutting the fourth side of my pond was flat rather than sloped I would probably have gone ahead and edged it with the turf, notwithstanding any dire warnings about leeching of mud into the water etc. It would only have been a foot of liner under the grass at most. However, since last night when I first posted, its occured to me that there's another issue to consider. Our garden is heavy clay, and when clay gets wet and goes downhill it can make a helluva mess. Therefore, rather than risk the pond taking on a permanent brownish tint, I've decided to look for a different solution.

    Glad to hear that your turf edging has been a success, of course. image

  • Tracey KTracey K Posts: 46

    Grow something along the side that will hang over. There are shaped slate stones all around mine but you can't see them on the right, in summer, for the Nemesia. Flowers drop in - but they net off easy enough.


  • DesthemoanerDesthemoaner FlintshirePosts: 182

    Thanks, Tracey.

    I'll probably use coping stones for that fourth side, and carefully mortar them in place for security. Something growing across them to conceal what is otherwise likely to look like a pig in a poke is an excellent idea. 

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