How to build a pond
It is thought that some amphibians, such as frogs, are now more common in garden ponds than in the countryside. You can build a pond any time during the year, but if you start in late winter it will establish quicker.
You will need:
A big patch of garden
A plank of wood
Pond liner - we would recommend a liner made of butyl rubber, which is durable, flexible, moderately cheap and easy to work with
A variety of pond plants
A spirit level
Sand -sand is excellent because it is sterile and will not harbour any undesirable seeds or microbes
Water (use rainwater for best results)
How to build your pond
It is better for wildlife if you put the pond in a warm area, tadpoles, dragonflies and plants with thrive in these conditions.
Mark out your pond on the ground with a rope or hosepipe first and then get digging! Dig the hole, ensuring the sides are level with a spirit level on a plank spanning the pond. Remember to include some shallow areas.
Remove any sharp stones from the bottom of the hole and first put down a 5cm+ layer of sand, old carpet or newspapers (or try loft insulation material!). Save some sand for step 4.
Dig a trench around the edge of the pond for the overhanging pond liner to drop into. Lay the edge of the liner into this and weigh it down with large rocks. Any extra excess liner can be snipped off with scissors.
Fill the bottom with the remaining sand.
Fill the pond up, this may take longer than you think. If possible, use collected rainwater to fill your pond; for most people however, filling from the tap with a hose is usually the most practical method. To stop the sand substrate dispersing, rest the nozzle on a plastic bag to absorb some of the energy. If you fill it from a tap or a hose your water might turn green - don't worry, this is just the minerals.
Back fill the trench with soil; as the pond fills up, the liner will stretch. As the pond is filling, place turf, soil or flagstones over the exposed liner at the pond edges. Butyl liner degrades in sunlight so try not to leave areas of uncovered liner exposed for too long.
Plants can be introduced to your pond approximately 1-2 weeks after the initial filling with water, when tap water nutrients such as chlorine and fluoride have evaporated. Carefully selected native species (see below) will support your local wildlife.
Watch and see what wildlife visits. Place stones, logs and plants around the edges to create some habitats for all those future pond visiting creatures. Consider adding a plank of wood to help any wildlife that might fall in.
If plants are well chosen and the pond is kept in a relatively balanced ecological state, it shouldn’t need very much maintenance at all. However, do keep an eye out for a build up of dead organic matter and encroaching vegetation.
Choosing pond plants
There are four 'zones' in which pond plants may be grown; try to have plants in each zone.
- Totally submerged (in deeper water) - oxygenating plants
- Submerged but with floating leaves (also in deep water) - oxygenating plants
- Emergent (in shallower area)
- Marginal (growing in the pond edge and bog areas)
Pond plant lists
Here are some recommended plants.
- Spike Water Milfoil Myriophyllum spicatum
- Hornwort Ceratophyllym demersum (pollution intolerant)
- Shining Pondweed Potamogeton lucens
- Horned Pondweed Zannichellia palustris
- Fennel Pondweed Potamogeton pectinatus (pollution tolerant)
- Water Starwort Callitriche stagnalis (pollution intolerant)
- Water Crowfoot/Buttercup Ranunculus aquatilis (pollution intolerant)
- Bladderwort Urticularia spp
- Frogbit Hydrocharis morsus-ranae
- Broad-leaved Pondweed
- Potamoeton natans (pollution tolerant)
- Curled Pondweed Potamogeton crispus (pollution tolerant)
- Branched Bur-reed Sparganium erectum (tall; can be invasive, but a good alternative to Typha)
- Amphibious Bistort Persicaria amphibium
- Arrowhead Sagittaria aquatilis
- Water Crowfoot Ranunculus aquatilis
- Water mint Mentha aquatica (can be invasive: also strong scent deters some insects)
- Flowering Rush Butomus umbellatus
- Water Plantain Alisma plantago-quuatica (tall)
- Water Forget-me-not Myosotis Scorpiodes
- Stinking Iris Iris foetidissima (tallish)
- Marsh Cinquefoil Potentilla palustris
- Swamped grasses - good for pond invertebrates
- Flowering Rush Butomus umbellatus
- Lady's Smock Cardamine pratensis
- Marsh marigold Caltha palustris
- Purple Loosestrife Lythrum salicaria (tall; a wonderful bee plant)
- Gipsywort Lycopus europaeus
- Sedges large and small
- Meadowsweet Filipendula ulmaria (tallish; good for birds in autumn)
- Brooklime Veronica beccabunga
- Ragged Robin Lychnis flos-cuculi
- Soft Rush Juncus effusus
- Water Forget-me-not Myosotis scorpioides
- Bungle Ajuga reptans
- Water Avens Geium rivale (spreading)
- Marsh Woundwort Stachys palustris (tall)
- Great Willowherb Epilobium hirsutum (tall)
- Hemp Agrimony Eupatorium cannabinum (tall)
- Fleabane Pulicaria dysenterica
- Rough grassland with Creeping Bent Agrostis stolonifera
- Marsh foxtail Alopecurus geniculatus
- Fool's watercress Apium nodiflorum
- Common Spike-rush Eleocharis palustris
- Water pepper Persicaria hydropiper
- Silverweed Potentilla anserina
- Creeping Jenny Lysimachia nummularia (low growing ground cover)
- Water Dock Rumex hydrolapathum (may be invasive)