Louise Curley

27 Apr 2022 15:23

Build Your Own Pond


Text and photo: Louise Curley 

One of my lockdown projects last spring was to build a pond. Wildlife experts say one of the best things you can do in a garden is to find space for a pond no matter how big it is – even a small container filled with water will attract wildlife. I don’t really have a lot of available space for a pond, but there was one corner of the garden that I didn’t really know what to do with it. I’d thought about putting a bench there or a sculpture, but in the end it seemed like a good place for a pond, albeit a small one.

There are lots of options when it comes to making a pond. You can use a container either sunk into the ground or raised above it, you can dig a hole and use a preformed rigid liner or line the hole with a flexible pond liner. I chose the flexible pond liner option, as it meant I could make the pond fit the space rather than being restricted to the size and shape of a container or rigid liner.

When making the hole it’s important to create different levels – the centre of the pond should be the deepest spot and then around the edges make ‘shelves’ using compacted soil. These different levels mean it’s possible to grow different types of aquatic plants, as some prefer to be in shallow water and others need deeper water.

Before putting in the flexible liner add a layer of sand to the bottom of the hole, patting it down to create a smooth surface. The layer of sand stops stones from puncturing the liner. Then, on top of the sand, add a layer of fleece fabric which also protects the liner. Finally position the liner in the hole, folding the excess material. It’s a bit like wrapping an awkward present and not knowing what to do with the wrapping paper, but once you get started it tends to fall into place. Before you cut around the edge to remove the excess pond liner, fill the pond with water as the liner will sink under the weight of the water, then once it has settled you can cut away the liner around the edges.

I hid the edge of the liner with stones that I’d found in the garden and then it was a case of adding the plants, which is always the best bit.

The soil around the pond is heavy clay which holds on to moisture and in prolonged wet spells it doesn’t drain very well, so I chose plants that were happy to be in moist soil. The grass Carex muskingumensis has attractive zingy bright green upright leaves; Geum rivale, a native plant that grows near water, has pretty drooping, pink flowers in late spring and early summer; a couple of candelabra primulas have tall magenta blooms; and there’s a white-flowered marsh marigold.

In the pond there are two irises, a yellow-flowered marsh marigold, the fibre optic plant, Isolepsis cernua, and several oxygenators: hornwort, water forget-me-not and Oenanthe javanica ‘Flamingo’. It’s lovely seeing the pond spring back into life now that the weather is warming up, although the rising temperatures can mean algae can start to grow in the pond, so it’s a good idea to add a dose of barley straw extract every couple of weeks from now until autumn.