Wetlands and ponds are a natural element of the British landscape; sadly they have been disappearing rapidly over the last 100 years mainly through drainage and of those remaining, many are polluted by agricultural and industrial run off. Garden ponds can help to replace the habitat that is still being lost.
Ponds support a wide variety of flora and a wealth of aquatic animal life. They attract insects, birds, frogs, toads and newts as well as providing a watering hole for wild and domestic mammals. They are beautiful, peaceful and educational. It’s fascinating to watch the antics of breeding frogs in March, to look for the black, pearl like strings of toad spawn, to catch a glimpse of a water boatman paddling beneath the surface, to see pond skaters skimming across the water, to observe dragonflies landing on marginal plants and to catch birds bathing in the shallows. Evaporation from a pond can also help mitigate the urban heat effect, cooling the air around them. A watery oasis is the single most important element you can introduce to increase biodiversity and improve the environment for wildlife in your garden.
Ponds can be anything from an old sink or half a wooden barrel to a large excavated area lined with butyl rubber. They work best in a sunny and sheltered area without overhanging trees that may shed leaves into the water where they rot and reduce oxygen levels. It is best to fill them with rainwater to avoid algae blooms and clouding, so erect a water butt to collect rainwater draining from a roof to fill them. The larger the pond, the greater the variety of species it can support and the easier it is to maintain a balanced state and clear water, but even a small pond will benefit wildlife. A pond to a depth of around 60 cm will support many aquatic species with most living or growing in the shallow areas. It is important to include a shallow sloping area, possibly covered in gravel or stones, to allow both amphibians and mammals that may have fallen into the pond, to climb out.
There is a wide range of native aquatic plants, some of which are particular to London. There are also introduced water plants, best to be avoided as they are escaping into the environment and threatening local ecosystems. Several planting zones need to be considered, beyond a clear area, preserved to watch dancing newts, wriggly tadpoles and busy water boatmen. Central to aquatic ecosystems are the oxygenators that create the environment needed for other species to live. The soft green whorls of Hornwort Ceratophyllum sp., feathery Water Millefoil, Myriophyllum sp., the tiny leaves of Water Starwort, Callitriche sp., and crinkly leaved Curled Pondweed, Potomageton crispus can all be used. Around the shallow edges are the marginals, creating protection, places for small creatures to hide and leaves where others may lay their eggs. Dramatic Flowering Rush, Butomus umbellatus, aromatic Water Mint, Mentha aquatic, bright yellow Marsh Marigold, Caltha palustris and Purple Loosestrife, Lythrum salicaria. In deeper water, there are plants with roots at the base and floating leaves; the White Water Lily, Nympaea alba, Bogbean, Menyanthes trifoliate, delicate, pale blue Water Forget-me-not, Myosotis palustris and Water Soldier, Stratiotes aloides.
Using one or some of each of these plants and a variety of water depths will create a rich habitat, welcoming aquatic creatures that will find there way on the leaves of pond plants, the feet of birds or through other gardens to a new watery place. Foxes and hedgehogs will delight in finding a watering hole and birds will be able to splash at the margins. The pond will soon be teeming with life.
Ponds and watery places to visit
The London Wildlife Trusts Centre for Wildlife Gardening
The Centre for Wildlife Gardening in Peckham, south London, is the perfect place to learn and relax in a welcoming outdoor environment. The Centre's demonstration wildlife garden has a range of mini-habitats including four ponds, chalk bank, wildflower meadow, woodland copse, herb garden, stag beetle sanctuaries, insect hotels and raised beds demonstrating permaculture.
28 Marsden Road, London SE15 4EE
The London Wetland Centre
An urban oasis for wildlife and people, just 10 minutes from Hammersmith. Stroll among the lakes, ponds and gardens.
Queen Elizabeth's Walk, London SW13 9WT