Slate Flagstone?

Discussion in 'Newbies to Garden Ponds' started by AngelaM, Oct 15, 2017.

  1. AngelaM

    AngelaM

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    My original plan is to surround the outer edge of my pond with flagstone rocks. I'm running into issues trying to get them to lay correctly on the liner that overhangs outside the pond. Plus some stones are thinner than others so I need to raise them up with a bit of sand or something. My only concern is all this sand going to end up in my pond the first time it rains? I do have a slight angle along the edge of the pond tapering away from it so things wash away from the pond instead of into it. Has anyone used flagstone around the entire edge of their pond? Do you have any helpful tips? Should I trim the liner back some? It overhangs 2 feet in some spots but I thought it would make a good weed barrier. I eventually plan on planting moss between all the flagstones.
     
    AngelaM, Oct 15, 2017
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  2. AngelaM

    addy1 water gardener / gold fish and shubunkins Moderator

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    I did that with my Arizona pond, had flagstone lining the stream and the pond. Used sand and crushed granite to level them. The pond edge was a bit higher, no sand or granite got washed into the pond.

    It looks very nice, in az though hard to get anything to grow between the stones.
     
    addy1, Oct 15, 2017
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  3. AngelaM

    sissy sissy

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    But heavy rains and even lots of snow melt will shift the slate around the pond .The freeze and thaw times will really be the hardest on slate shifting .My slate shifts on a area where I put a bench and I live in VA 101_1193.JPG
     
    sissy, Oct 15, 2017
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  4. AngelaM

    AngelaM

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    Do you think I should use grout in between to cement them in place? All of my pieces of slate are pretty heavy and big. I wonder if that would keep them from shifting. The smallest pieces are about 10"x10".
     
    AngelaM, Oct 16, 2017
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  5. AngelaM

    Angel

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    you can always try 1 year dry fit stack and then if needed grout etc
     
    Angel, Oct 16, 2017
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  6. AngelaM

    brokensword Not all those who wander are lost

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    No, it won't matter; the ground heaves when it freezes. The only way to stop your slate from moving would be to have a footing that is deeper than your frost line. Just let them be and periodically tweak them back into place.
     
    brokensword, Oct 16, 2017
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  7. AngelaM

    Lisak1

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    We laid our flagstone steppers into a sand base in our path to keep them from moving. So far no heaving or shifting at all after two winters. We also built a small flagstone pad for our pond viewing bench and used a sand base plus Powerloc Jointing Sand between the stones to create a more solid surface. That has also held up well for amateur work.

    As for the liner, I don't know that I would try to lay the slate over the liner. Are you trying to get the slate to overhang the pond edge slightly? Or just create a path?
     
    Lisak1, Oct 16, 2017
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  8. AngelaM

    sissy sissy

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    I live in southside Va and mine shifts in the pic I showed .I used paver sand and the stuff they sell that you wet and it is supposed to stop that .Well not
     
    sissy, Oct 16, 2017
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  9. AngelaM

    CometKeith

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    Hi Angela. I have always used flagstone to edge my pond. Usually I use larger pieces than 10x10 so they are heavy and don't move. Also kids and animals try to walk on them so the heavier you have them the better. We don't have any small children, but we sold something on Craig's list and their children promptly jumped on the flagstones to get a better look at our fish! I was glad they were in the ground solid. I have always sat the flagstones directly on the liner, If some are thinner or the liner is too low I usually just raise the ground under the liner up by adding dirt or even a brick. If I need to level the flagstone a little on top of the liner I have used pea gravel or small round edge rocks under it which works pretty well. You need to wash pea gravel before you use it because they are pretty dusty. If some pea gravel falls in the pond it won't hurt anything. I use pea gravel in my planting boxes in the pond too.
     
    CometKeith, Oct 17, 2017
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  10. AngelaM

    sissy sissy

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    Only bad thing with pea gravel is a fish will sometimes swallow them and they can get stuck and cut off air to the fish .I saw it here one time and it was hard as heck to get the stone out of a fish mouth .My neighbors grandson threw pieces of pea gravel in the pond and the fish thought it was food .I think they spit most out but one fish was acting funny and only thing I could think of was gravel was stuck and it was .Glad she caught it right away and I was home .Not an easy task either .I guess some fish are not very smart .;)
     
    sissy, Oct 17, 2017
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  11. AngelaM

    CometKeith

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    Hey Sissy. That sounds a little unusual. I have never thrown in pea gravel and my fish have never ate it. i guess there can be an issue with almost anything but I think pea gravel is very safe. Except when I moved and my construction workers let almost anything go in the pond I generally have at least 98% of my fish make it from year to year. Just yesterday I had to stop one of my guys that was spraying waterproofing solution because it was so windy that some of it was flying towards my pond.
     
    CometKeith, Oct 20, 2017
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  12. AngelaM

    mgmine

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    I have flat rocks not flagstone and it lays directly on the liner. Between the stones I planted sedum and it looks nice. Since flagstone is thinner and lighter you might want to keep it from overhanging the edge or at least only overhang a little. I wouldn't use sand or anything else. As far as trying to make them level I would sink the thicker ones instead of raising the thinner ones.
     
    mgmine, Oct 20, 2017
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  13. AngelaM

    sissy sissy

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    I had seen it a couple of times here where gravel got suck in a fish .I guess some fish are not very smart when it comes to gravel .Had one here about 3 weeks ago that called me that had taken in some rescue fish I had given them .There grandson had thrown some pea gravel in the pond and 1 piece got stuck in fish throat and they could not figure out why fish was not eating but his mouth was open .It was a larger piece stuck in fish mouth .Not easy to get out believe as this fish was bigger .It was like when I wrestle my chihuahuas to get their toenails cut .:);)except they are not wet and slippery .
     
    sissy, Oct 20, 2017
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  14. AngelaM

    IPA

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    I bought some Santa Fe flat stones for the border, just placed on top of liner. My dog gets excited when the fish eat trying to get to them and knocked one into the pond. As it fell to the bottom, straight sides, I could only imagine the hole it was sure to create. Fortunately I dodge that bullet but will be looking for a way to secure them to prevent any more incidents.
     
    IPA, Oct 21, 2017
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  15. AngelaM

    AngelaM

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    Yes I'm trying to let the slate slightly overhang the edge of the pond.
     
    AngelaM, Oct 24, 2017
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  16. AngelaM

    AngelaM

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    So I think I'll use the larger heavier pieces around the edge and the smaller pieces furthest from the edge that way they don't get knocked in the pond so easily.
     
    AngelaM, Oct 24, 2017
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  17. AngelaM

    addy1 water gardener / gold fish and shubunkins Moderator

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    When you place them have the pond edge slightly tipped up, i.e. the non pond edge just slight dug in. It helps keep them from slipping into the pond.
     
    addy1, Oct 24, 2017
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  18. AngelaM

    AngelaM

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    Thanks! That's exactly what I was thinking too. I do have a pretty good slope leading away from the edge of the pond to prevent any runoff from entering the ponds. That should help kee the slate from falling in. I was just wondering if the slate will slide around on the excess liner that hangs over the pond edge. How much excess liner should I allow to hang over my edge anyways?
     
    AngelaM, Oct 27, 2017
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  19. AngelaM

    addy1 water gardener / gold fish and shubunkins Moderator

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    You can fold it under. I tend to not trim liner, seems like down the road you may need it.
    Did you dig a shallow shelf to place rocks on? Like two inches under the water. The rocks would be partly in the water, partly out. A great way to hide the liner coming out of the pond. Those rocks on the shallow shelf would help support the pond side edge of the flagstone.
    The frogs love to sit on those rocks.

    upload_2017-10-27_7-48-22.png
     
    addy1, Oct 27, 2017
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  20. AngelaM

    ZEROPILOT Faster than you are.

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    I used "stones" made of cement that I got at the Home Depot and used mortar to set them in. The mortar filled in the gap and once set, made to whole edge of the pond super sturdy. Sturdy enough to support my full weight. And I ran my plumbing underneath it.
    Once they've aged a bit, I'm thinking that both the "stones" and the cement will look natural(ISH) and I'm thinking that creeping vines, etc will grab onto the cements rough texture.
    (Oh, and these are also a lot cheaper!)
     

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    Last edited: Oct 27, 2017
    ZEROPILOT, Oct 27, 2017
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