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Overwintering the Garden Pond

October 28th, 2011

If you remember, we have a small garden pond that we put in last spring. It used to reside in my parent’s garden, until they replaced it with a much larger pond. We put fish in it last year, which promptly all got the ick and died. They were replaced with fish from my parents pond that survived for quite a while, then died right before winter.

This spring we put 10 small feeder goldfish in the pond; they all survived. Now I’m wondering if I need to put a small heater in the pond for winter. My parents always had fish survive in the pond, but they had a spring running into it which kept it from freezing. I know it doesn’t freeze through to the bottom because my water lily survives, but I’m wondering if the fish will survive.

Does anyone have any advice for me on what to do with this pond over the winter? heater, on heater? We live in a zone 5a, so it can get pretty cold in the winter.

What zone is your garden in? Do you deal with cold or heat as your most extreme temperature?

16 Comments to “Overwintering the Garden Pond”
  1. Deborah on October 28, 2011 at 7:00 am

    I think it comes down to how deep your pond is, even if there is just a pocket that is deeper than the rest, it really improves your chances. If you are sure your pond doesn’t freeze solid, than the fish will hunker down in the sediment at the bottom and they will be fine. Occasionally, if the pond has been frozen for a few days without thawing, you should melt a hole in the ice to allow trapped gases to escape, perhaps using a saucepan filled with boiling water, etc.

    You are colder out there than we are here on Long Island, but I have had fish in our pond for 12 years now. They started as feeder fish, and now some are 8″ long!

    Good luck!

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  2. Corrie on October 28, 2011 at 7:40 am

    Zone 5b here, and the fish always survive in the very bottom of our pond that looks very similar in size to yours.

    In Southwest Ohio, I think we get the best of both extremes, heat and cold. I know it will always be hotter somewhere, and colder somewhere, but we kind of get it all in the course of a year.

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  3. Mich on October 28, 2011 at 7:45 am

    Afraid I have no idea how your zoning works; but your fish should survive freezing temps – you just have to make sure the surface doesnt stay frozen over.
    In one of my work gardens I put a football/tennis ball on to keep the surface from totally freezing.
    Fish seem to survive and we had -12c last winter. brrr.

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  4. Ryan on October 28, 2011 at 8:01 am

    We have had ponds for years. Rather than use a heater we would put in a airation stone, it adds oxygen to the water, and keeps a solid sheet of ice from forming. Place it about a foot below the surface as you don’t want to set up a current that goes takes the warmer water up to the top to cool.


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  5. Nebraska Dave on October 28, 2011 at 8:10 am

    Susy, my Mom had a nice rock garden with a pond that had a little bridge over it so it seemed like there were two ponds. We put goldfish in the pond and brought them inside in washtubs for the winter. It gave us a chance to clean out the ponds as they were under Maple trees and during the fall it would all but fill the pond with leaf drop. I think we had fish in the pond only a couple years as they are quite a bit of work. At least it seemed that way for a teenager who had other things on the mind. Cars, cars, I had cars on my mind. :0)

    Have a great fish pond day.

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    • Barbara Shaw on October 25, 2012 at 8:50 pm

      Many years ago, when I was a child our friend had several goldfish ponds. In the winter they would bring all the fish in side. They used large glass jars and they put them on the mantle where they had an open fireplace, no central heat!. They were beautiful. I remember watching them when we visited.

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  6. Becca on October 28, 2011 at 9:06 am

    I agree with the aeration. The fish need the extra oxygen during the winter and don’t feed them b/c their gut stops digesting as quickly in the cold weather and the food could rot inside before it’s digested! How deep is your pond? That has to do w/overwintering as well. I had a tropical frog that died here during one of our winters (and we’re 8b).

    Reply to Becca's comment

  7. gabe on October 28, 2011 at 9:27 am

    Up here on the east side of Cleveland, I had a pond at my old house (haven’t gotten one in at the new place yet). It wasn’t anything big – maybe two feet deep at the deepest point, and four feet across, and I never did anything special with it. It froze, but never more than six or eight inches down – I think we’d need a really long period of arctic weather, which we typically don’t get here, to freeze the whole thing. Once the top several inches get frozen, the ice almost acts like insulation for the rest of the water beneath it – it takes much longer, colder periods to freeze the next three inches than it does the first three.

    Anyway, I put a dozen or so feeders in there one spring, and most of them survive the winters, and in fact, have produced babies. I don’t make holes, or aerate – once it freezes, it’s frozen until nature thaws it out. Then come spring, I eventually see those flashes of orange again.

    Sorry that was such a drawn-out answer. Basically, yes, it just depends on how deep you are. If it’s more than a foot or foot-and-a-half, you should be fine.

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  8. Trish on October 28, 2011 at 9:47 am

    I live in zone 6 and both my Dad and I have fish ponds, his is much larger than mine.I have had mine for over 10 years and have never had a problem with loosing fish during the winter from freezing. It will freeze pretty solid. I always am amazed to see the fish come back in the sping especialy after last winter that seemed particularly harsh. Way back, when doing research for this project I read somwhere that your pond should have one area that is at least 3 feet deep for the fish to hunker down in.
    One thing that my Dad does. he covers his with what looks like a giant wood pallet covered with plastic that he made. This is mostly to keep out the fall leaves. Hope this helps

    Reply to Trish's comment

  9. Shaun on October 28, 2011 at 10:07 am

    A neighbor with a pond here in Colorado keeps a vertical pipe in the pond and during extra-cold spells will put a hot teakettle full of water inside the pipe to help regulate the temperature a bit. They’ve had good success with fish survival (except when the herons come). Might be a good idea to research that idea more.

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  10. Grannie M on October 28, 2011 at 10:08 am

    I’ve had a garden pond 3 yrs. and live in Southern Iowa, zone 4-5. My pond is about 30″ deep in the middle. First year, I overwintered fish in basement in an old cattle tank and added my pond pump and surrounded it with my larger plants. I enjoyed the sound of the water all winter, but my DH didn’t. Second year I left them in the pond, and they and all the native frogs died. Last year I used an electric heater. They wintered ok, but too costly. This year I’ve decided to try a cattle tank in my unheated greenhouse as it will be easier in out of the wind to open a hole in the ice as needed through the winter. I will also be able to add suspend a lower wattage bulb for heat over the tank if needed.

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  11. goatpod2 on October 28, 2011 at 11:03 am

    It gets cold here and HOT as well but we never put a heater in our pond during the winter months and our feeder goldfish have all survived though.


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  12. plantingoaks on October 28, 2011 at 11:15 am

    My grandparents have a pond in your zone, no heater, maybe the size of an average bath tub. It regularly freezes.

    Feeder goldfish generally survive the winter, though not 100%. They have more losses from raccoons and other predators than weather though.

    Reply to plantingoaks's comment

  13. Victoria on October 28, 2011 at 7:19 pm

    We’re 7-8 in Maryland. The past few years we’ve had a lot of snow from Dec-Feb, but the temps never stay below 15 for long. My son’s preschool has an outdoor pond with some large fish. We’ve noticed that the fish stay fairly deep in the winter months, but I’m not sure if it’s heated.

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  14. Sofie Dittmann on October 28, 2011 at 7:42 pm

    My dad used to bring his inside, despite the fact they don’t get the same winters anymore in the old country that we get here.

    Reply to Sofie Dittmann's comment

  15. KimH on November 1, 2011 at 4:54 pm

    We’re in Zone 6a since we live just a block from Lake Erie. Winter cold is our most extreme weather climate to deal with though to be honest, I dont have many problems here.

    M’honey was planning on putting in a little pond, but it hasnt been on his list of priorities, so I’ve absconded with his space. Haha.. thats where Im gardening these days. ;)

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This is a daily journal of my efforts to cultivate a more simple life, through local eating, gardening and so many other things. We used to live in a small suburban neighborhood Ohio but moved to 153 acres in Liberty, Maine in 2012.

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