Forum home Wildlife gardening

Wildlife pond advice


I'm in the process of planning a wildlife pond, hopefully to be built later this year or early next year, it's going to be a very rough crescent shape, aprox 3m x 2m and around 0.8m deep at it's deepest point. I'm using a flexible liner with an underlay, on a sand bed

the advice I'm looking for what's the best type of sand to use ? ie building sand, sharp sand or another type and how deep does the sand need to be ?

thankyou for reading




  • Gary HobsonGary Hobson Posts: 1,892

    The type of sand doesn't matter at all. The sand simply helps to provide a flat bed so that any no sharp stones don't puncture the liner.

    The thickness you need depends on how smooth you can make the bed beneath it. If you have the patience to make a smooth surface, you don't need sand.

    Even with sand, it's important to inspect the bed of the pond carefully, and to remove any sharp stones, or hard bumpy nuggets of soil. Soils such as clay may contain a lot of flints, which have sharp edges. It's important to remove them.

  • weejennyweejenny Posts: 386

    Hi John, Ive done a couple of ponds now. I think you'll regret not doing it deeper, once its done thats it. Its a great project I loved my ponds we moved house and have no room for one now. We had a great diving water beetle in ours its the scariest beetle you'll come across, google them

  • Yup, if I had my time again I would have gone deeper on the digging....anything over a metre is ideal but the deeper the better.  I used old carpet to line the pond before the liner went in but as Gary says, it's mainly to stop sharp stones (and those ever-present bits of blue and white china) puncturing the liner.

  • HyppyBykerHyppyByker Posts: 146

    Ditto on the depth and I sloped the edges too much on too wide an area to allow for the wildlife getting out but not the depth for plants image

  • FloBearFloBear Posts: 2,281

    Agree with deeper in one section of the bottom at least. I've found about a metre is fine. Like Boticelliwoman I used carpet - actually mostly underlay - as well as sand.

  • Thanks for the replies

    I can go deeper, but I was a little worried about the sides of the pond being too steep. The area for the where the pond is going in, is aprox 5m x 3.5m, so I don't really want to make the pond any bigger, the area around the pond will also be an extention to my wildflower garden.

    I'm not sure what my soil is like, at a metre deep, nearer the surface it's quite good soil. But around where I live there's a lot of clay type soil as you go deeper.

    Sorry another question but is there a maximum angle for the sides of the pond ? without having to build any type of a retaining wall

    thanks again


  • weejennyweejenny Posts: 386

    it doesnt need to be same depth all over i did over a metre just to one side and a metre on other. mark out the shape you want with your garden hose dig down to the depth you want and when youve done that back breaking bit(I was lucky our neighbour had a jcb and felt sorry for us werent we lucky it reached into our garden) Then you do a shelf within your shape for sitting baskets of water plants about 25cm down, make sure its wide enough(and flat enough) to hold your baskets or they may tip into the pond! this shelf only has to be to one side just decide on yor planting and of course this shelf is also for wildlife to get in and out of the pond I softened my edge with stones of all sizes this also helped wildlife. I used boulders to soften the edge of the pond. Another tip is to use a long spirit level put a plank of wood across the finished levels before you put down your liner, if its not level you'll see the liner which is unsightly and it will get sun damage.Do it again when the liner is in you can always pad up an area with sand to get levels right. It is so important to prepare the pond carefully as it can look awful if not right . Good luckimage Im so jealous

  • Thanks again for the advice

    I'm hopefully going to get it started this autunm, which gives me time to get my plans right and to save some pennies. I'm affraid mine will have to be all dug by hand, the only access to the garden is via some steps so a mini digger is out of the question.

    thanks, no doubt I'll be after some more advice before I've finished


  • weejennyweejenny Posts: 386

    looks like you'll have a few raised beds about too..Thats alot of soil to dig out happy digging. Why dont you have a digging party it might be worth a bbq and a few botttles of wineimage

  • You can just stick with your first plan and then dig a deeper hole somewhere in the middle or at one end.  The point of the depth is so that over-wintering amphibians have a safe place in the mud that won't get frozen.  However, you do need to make sure that there's no rotting vegetation in the pond as this seems to cause a build up of toxins if the pond is frozen over for any length of time.  When we had the bad winter a couple of years ago, hundreds of frogs died in garden ponds and research showed that:
    a) a hole should be kept open in the ice at all times
    b) any snow laying on top of the ice should be cleared as the lack of light prevents plants oxygenating the water
    c) ponds should be cleared of as much dead organic material as possible before winter


Sign In or Register to comment.