Choosing a site

The correct siting of a pond is essential for its success. A healthy natural balance results from lusty aquatic plant growth and this only happens in an open sunny position. Avoid the close proximity of trees. Not only do they provide troublesome shade, but fallen leaves will contaminate the pond as they decompose.

What size pond?

There is no ideal overall size for a garden pond, although the larger it is within reason the easier it is to maintain a good ecological balance. The water temperature is much more stable in large bodies of water. However, there are specific depth requirements for aquatic plants and decorative fish. Marginal plants require shallow ledges around the edge of the pool. These should be about 23cm (9in) deep and of similar width if they are to accommodate aquatic-planting baskets properly. Waterlilies and other deep-water aquatics can be positioned in the deeper central area. This should be at least 38cm (15in) deep, especially when intending to over-winter fancy goldfish.

Pond liners

Pond liners are the most popular form of pond construction. They consist of a sheet of rubber, PVC or other waterproof fabric, which is placed into a carefully prepared excavation and moulded to its contours when water is added.

Pre-formed ponds

Pre-formed ponds are of a pre-determined shape, usually with deep areas for waterlilies and shallow shelves for marginal aquatics. They are installed by digging a hole larger than the pre-formed shape and then carefully backfilling, at the same time ensuring that the pool is positioned absolutely level.

Stocking a garden pond

When stocking a garden pond it is important to remember that a whole new underwater environment is being created in which plants, fish and snails depend upon one another to provide the basic requirements necessary for a harmonious co-existence.

Submerged oxygenating plants replace the oxygen that has been lost to respiration but more importantly compete with slimes, algae and other primitive forms of plant life which can turn the water thick and green. Submerged plant life mops up excessive nutrients in the water thereby preventing troublesome algae from becoming established.

Plants with floating foliage assist by shading the surface of the water. This makes life intolerable for green water discolouring algae by reducing the light directly available to them. The marginal plants, although of no great importance in creating a balance provide the necessary colour to make the pool a continual source of pleasure.

When planning the planting, bear in mind the quantity of each type of plant necessary to create a balance, and then select within these limits those that have a particular personal appeal.

At least one third of the surface area of the pool, excluding the marginal shelves should be covered with floating foliage. This need not be composed entirely of floating aquatics for waterlilies and other deep water aquatics provide considerable cover with their floating leaves.

Initial stocking with submerged oxygenating plants is recommended at one to every 2sq ft (0.18 sq m) of surface area, evenly distributed over the pool floor, and with fish 2in (5cm) of length inclusive of tail to every square foot (0.09sq m) of surface area.

Snails of the flat curled ramshorn type can be introduced liberally and as marginal plants are of little significance in attaining a correct balance these can be planted freely.

Garden Pond Maintenance - All year round

Spring

• Pond plants can be planted and established waterlilies and marginal aquatics divided when necessary.
• If the pond requires cleaning only do so during spring.
• Introduce fish during late spring to a new pond.

Summer

• Control filamentous algae by twisting out with a nail through a stick.
• Cut off the faded blossoms of marginal plants.
• Net off surplus floating growth of carpeting plants like fairy moss.
• Fertilize the growing mediums of established waterlilies and marginal plants in early summer using a slow release fertilizer or specialized tablet or sachet form of aquatic plant feed.

Autumn

• Collect and store plantlets and over-wintering buds of those aquatics which benefit from winter protection indoors.
• Net the pool to keep out leaves. An accumulation of decomposing leaves will produce noxious gases which can be harmful to fish.
• Cut back all faded aquatic plants, but do not cut hollow stemmed marginals below water level or else they may rot.

Winter

• Ensure an ice-free area on the pond by the use of a pond heater to permit the escape of accumulated gases, which may become trapped and harm the fish