Plan your pond
The size of your pond will obviously depend on the size of your garden, and how and where you place it will depend on what kinds of wildlife you would like to attract. In general though, a good wildlife pond will have gently sloping sides to create the ideal conditions for amphibians to spawn, a place for birds to drink and bathe, and an escape route for accidental visitors like hedgehogs. A variety of insects will also appreciate these shallower waters.
However, a good pond should also include deeper areas that are more than 60 centimetres deep to prevent freezing during a harsh winter. To an extent, the total surface area of your pond will determine the wildlife it attracts. While frogs will happily spawn in ponds as small as one square metre, toads and great crested newts prefer a larger watery home, above 15 square metres, and some species of dragonfly require a stately 50 square metres to breed. Generally speaking, the larger the pond, the more species you will find living in your garden.
A warm and sunny site is ideal for the majority of pond life, so be sure there is an open side when choosing the position. Low bushes close to one or two sides will provide welcome cover for amphibians and bathing birds, but trees can cause problems - mature trees will clog up your pond when they drop their leaves in the autumn, and growing roots of young trees may end up puncturing the lining of your pond. Try to leave a little wild area of vegetation next to the pond, or add logs or stones where tiny froglets and toadlets can shelter when they emerge.
The hard work
With your site chosen and a rough size in mind, it's time to dig your pond. Start by marking out the shape of the pond with pegs and string, then dig the soil out, setting the soil to one side. The removed soil can always be used to create a raised bed, or a cosy hibernation or basking area for amphibians, reptiles and even bees.
At this stage, it's a good idea to line the hole with old newspapers, sand or even old carpet, as this will help to prevent the liner being punctured. Polythene or rubber liners are available from most garden centres - simply calculate the required size as the width or length of the pond itself, plus twice its depth, plus 10 per cent. With your liner cut to the estimated size, lay it into the hole without stretching it tight, overlap the edges and weigh it down. A layer of sand or soil mix over the liner will help to prevent damage from the sunlight.
Then fill your pond, preferably with water from a water butt, or, if the British weather obliges, allow it to fill up naturally with rain water. It may take a little time for the liner to settle properly, but once it is filled, the weights can be removed. Any turf that you removed when digging hole can be replaced at the edges, covering the liner overlap and giving your pond a more natural edge.
Whether you choose to splash out on koi carp or are just keen to get wildlife into your pond, a few pond plants will be very welcome. Native plants can be bought from garden centres, and a mixture of submerged plants, floating plants and emergent plants - where the roots are submerged but the foliage rises above the water - will encourage all kinds of species to breed. The best time to introduce these is in winter.
If you plan to add fish, be aware that goldfish and larger species will eat tadpoles and you are therefore unlikely to find amphibians breeding in your pond. Smaller fish like sticklebacks and minnows can happily nibble on the odd tadpole without eliminating the population
For those just hoping for native wildlife to colonise their pond, it's really a case of waiting and watching. Once the pond is established, you'll be surprised how quickly the locals settle in!
Manage your pond
A well balanced pond will rarely develop any serious problems. Should blanket weed or another plant look like it is taking over, it can be thinned out carefully (not more than a third in the space of 12 months) and it's an idea to leave the removed plants at the edge of the pond for a few days to allow any wildlife to find its way back to the water.
Hot, still weather can also cause algal blooms, as can increased nutrient levels caused by a dense population of fish. In the event that these naturally occurring plants threaten the health of your pond, a commonly used fix is to pack barley straw into netted bags, and tie them to a plastic drinks bottle. Anchor the bags in the pond but allow them to float to the surface - the water circulation is increased as the bag is blown about, thereby reducing the algae problem.
All you need to do now is enjoy your pond. Many native species will be only too happy to make their home there, and children and adults alike will find it fascinating to watch them breed, grow and develop. Just remember that water, even a small pond, can pose a safety risk to small children, so always supervise them and take precautions to ensure they can't fall in.
Which species have you spotted in your garden pond? Leave your comments below...