A raised pond adds depth, character and interest to any garden. The extra height of a timber-built pond also makes it easier to get in and out of the water, for cleaning, feeding or maintenance tasks, so you can enjoy the pond more often. A raised pond will need to be lined with a pond liner to protect it from the soil and other elements and to make it suitable for holding water. You should check with the pond liner manufacturer that the type you are using can be used for a raised pond.
Ideally, the pond how to build a raised pond should be in a position where you can enjoy it easily, perhaps next to an outdoor seating area or within view of your kitchen window. It should be accessible to make it easy to clean, feed and maintain, and also be located close enough to a water supply to avoid the need for a pump.
Before beginning the build, use a garden hose or rope to mark out the pond shape and size. This helps to give you a better idea of the final result and will help guide you as you dig out the hole. You can also use a pond calculator to find out how much space your pond will take and make any necessary adjustments.
You can choose to use railway sleepers or a more traditional wooden decking for the frame of your raised pond. If you’re using railway sleepers, it’s important to ensure that they are fastened together securely and at right angles to each other for a sturdy base. You should also check that there are no screws or sharp edges sticking out that could puncture the pond liner.
Once you’ve chosen a location for the pond, dig a hole in the ground large enough to accommodate the finished pond and create a sloping marginal shelf for planting at the water’s edge. Line the bottom of the hole with a layer of pond underlay, making sure it’s evenly spread and free from bumps and sharp stones that might puncture the pond liner.
Unfold the pond liner on the lawn or another flat surface and, with help from at least one other person, carefully drag it over the pond. Work in a way that minimizes small folds and neatly tucks the liner into the corners of the pond.
If you’re using a plastic liner, you can finish off the inside of your raised pond by placing a layer of pond underlay over it. Once this is in place, you can add a layer of gravel and then the pond plants. It’s worth adding a few plants that can survive at the water’s edge, such as yellow flag irises (Iris pseudoacorus) and various rushes and reeds for an attractive natural look.
Once the pond is full of water, a thin layer of green slime will settle on its surface, but you can keep it at bay with barley straw or biomat filters and by stocking the pond with larvae-eating fish such as goldfish, mosquito fish and bitterlings. Nylon netting stretched over the surface discourages raccoons, and motion-activated sprinklers can scare off other pond visitors.
