The standard planted garden pond

Some of the most memorable ponds are those which look as though they have been planted by Mother Nature herself. Appearing as though generations of weathering and evolution have shaped an aquatic hollow, to nestle in true balance with its surroundings.

We too appear to be in tune with nature’s hand as, almost by instinct, we can soon pick out the man-made impostor from nature’s own creation. Nature is a perfectionist at positioning, landscaping and planting and to be able to splice a piece of the ‘real thing’ in our gardens, we too must address these same areas.

Positioning.

Unfortunately the task of positioning a pond is not as simple as asking the question ‘where would a pond occur within my plot of land if it were natural?’ Most natural ponds will form in hollows in the ground, where the land drains itself collecting to form a pool. But as most gardens are reasonably flat, this is not an option unless substantial landscaping can be carried out. Furthermore, such low lying plots tend to be areas where a high water table exists, making it difficult to install a pond or liner due to incessant rising water filling the excavation.

Although areas where water is naturally abundant are often well populated with trees, a garden pond should be positioned so as to avoid leaf-fall wherever possible. Particular attention should be paid to the more notorious trees whose leaves, blossom or berries may prove toxic if falling into a pond. These include poplars, oak, elders, willow and yew trees. Furthermore, keeping clear of trees should make digging a pond much easier by avoiding their roots. If tree roots are encountered and removed during the excavation then the tree may eventually suffer or subsequent years of regenerative root growth after installation could pose a risk of puncturing the pond at a later date.

Similar considerations should be made if planning a pond to be adjacent to other immovable obstructions such as walls and other boundaries. Avoiding these will again make digging much easier and will avoid disturbing foundations.

Near or Far?

The viewing point for a new pond will determine its ultimate location. Some prefer a pond installed closer to the house where it can be enjoyed form inside the house or conservatory. This makes getting an electricity supply to the pond relatively simple and the house will also offer a degree of shelter from the elements, particularly in winter. Issues to overcome when siting a pond close to a house include avoiding drains during construction and ensuring that the house does not shade the pond completely of the necessary sunlight.

A further consideration when deciding where to site a pond is what to do with the spoil that is removed from the hole. The spoil can quite simply be stacked behind the pond to form a raised area for a rockery or waterfall. It can be difficult to build a raised backdrop for a pond close to a house as the mound can soon look like a misplaced bump in the garden. It is easier to achieve a more natural feature with a raised rockery or waterfall when positioning a pond further away from the house. This provides a raised backdrop in front of which the whole garden can be presented.

In addition, a pond positioned further away from the house can be landscaped more easily to blend in with the rest of a garden and can form a separate aquatic oasis to a garden which must be visited specifically to be enjoyed.

Pond shape.

Taking an example from natural pools, you will notice that they are shaped very simply, with sweeping curves and edges, perhaps shelving gently to form a ‘beach’ area. A planted garden pond should aim to follow a similar style, avoiding nooks and crannies which will form dead spots of still water and also prove difficult when laying a liner, creating creases and folds and using up extra material. Dig your pond to suit the area of land available, keeping the perimeter smooth and gently sweeping.

Depth.

The depth of a planted pond will vary across its area. Shelving around the edge should allow at least 9” of depth below the surface to allow space for planted baskets. The shelving need not be continuous around the pond’s perimeter and deeper shelving can be constructed for larger marginal plants.

The centre of the pond will be the deepest, aiming for a minimum depth of 2 feet. If the pond is not sufficiently deep then it may be liable to freeze in winter to such an extent that only a limited amount of water will remain below the ice in which the fish are to survive. Furthermore, the greater the volume of water that is contained in a pond, the more stable its temperature, preventing it from cooling down or heating up too rapidly. A larger volume of water will also enable you to keep more fish in a healthy pond environment. The solution to pollution is dilution.

Stocking.

All coldwater ornamental pond fish are compatible with each other, but some are not compatible with a planted pond. Koi and ghost carp are notorious for being destructive to plants. Their inquisitive feeding behaviour leads them to investigate any soft substrate, which unfortunately includes planted baskets. These fish can also grow rapidly and to a great size, making them less suited to a balanced planted pond. Any of the goldfish varieties (excluding the fancy goldfish) can be stocked. These include goldfish, comets, shubunkins and all variations in between! Golden Orfe and tench also make worthy pond companions.

The pond is best stocked on the basis of the pond’s area rather than its volume as this best determines the pond’s capacity for fish. As the balance of every pond is different, there are no fixed rules regarding the stocking levels for ponds. A pond will be pushed to its limit when it is hottest and will accommodate more fish when the pond is overwintering. To be safe, you should stock with the hottest conditions in mind and in doing so, aim for 3 inches of fish (excluding tail) per square foot of clear water surface as a rough guideline.

As with any pond, stock gradually, a few fish at a time and monitor water quality to make sure that your pond remains in balance.

Pond Equipment

The beauty of creating a planted pond is that very little pond equipment is required to achieve a stunning result.

1. Pond. The two most popular alternative materials of making a pond are pre-formed fibreglass ponds or flexible PVC liners. Although the preformed ponds are shaped and ready to go, they tend to be more expensive than liners and are quite restricted in their design. A liner however puts you in complete control and can be bought to fit any excavation you choose to make, offering a lifetime guarantee of 25 years.

A liner is usually bought off-the-roll. The area required is calculated by measuring the greatest length and width and adding double the depth to the length and width giving the dimension of the liner required.

2. Pond Pump.

If the stocking of fish is likely to exceed what the pond can sustain naturally, then a water pump is required. If however you are only looking to stock a small number of fish in a planted pond then even a pump should not be necessary. As a pump will be working in partnership with the plants and the ecology of the pond, a small, internal foam filter should suffice, which is unobtrusive and easy to install. The pump can be fitted with a fountain head for effect if desired. If a larger filter is required, then an external box biofilter can be installed and used to feed a waterfall. The pump should be installed to circulate the pond’s volume once every 2 hours.

Planting

In a planted pond, the aquatic vegetation will play a number of roles in the pond.

1. Functional. The pond water will have a tendency to turn green or be invaded by blanketweed and just as in a garden border, desirable plants should be chosen to compete against these unwanted weeds. Many submerged plants can also provide spawning and nursery areas for fish and their fry.

2. Aesthetic. Plants should be chosen and placed within a pond to soften any harsh edges and to complement other features in the pond. For example, tall marginal plants should be placed towards the rear of the pond and low, sprawling marginals to the front.

There are hundreds of varieties of aquatic plant to choose from so it is more useful to categorise the different depths and zones within a pond where plants will thrive.

There are essentially 3 areas within a pond which can be planted.

1. Marginal plants on shelved areas.

2. Deepwater submerged plants on the pond bottom.

3. Surface or floating plants.

The majority of plants (except the floaters!) are placed in a plastic mesh basket which is lined with hessian or foam and filled with a heavy loam aquatic soil. The soil is then covered with a generous layer of gravel to prevent the soil from escaping and the basket is gently lowered to the desired position in the pond.

Pond Maintenance

Pond maintenance should be carried out on a basis of a little and often. A pond should never be completely emptied if at all possible, but maintenance carried out periodically to keep on top of necessary chores. Leaves should be removed regularly and the pond bottom should be cleaned to remove the inevitable build up of silt (using a pump or aqua-vacuum).

With minor tinkering, the balance of a pond is likely to be maintained which will help to keep the water, fish and pondkeeper healthy and happy for many years to come.

The Goldfish.

The goldfish can be regarded as the standard bearer of all ornamental fish. Initially kept and prized by the wealthy rulers of China over 1500 years ago, their legacy for us today is the world’s most widely kept pet, probably the first ornamental pet fish in the world to be cultured, the goldfish. Through the meticulous attention to detail associated with the advanced Chinese culture and civilisation all those years ago, goldfish were selectively reared from the dull, brown and visually unappealing native crucian carp to produce the simply beautiful fish we have today.

Varieties

To satisfy the demand for a wider range of goldfish forms, selective breeding of more exotic or ‘fancy’ varieties of goldfish has lead to there now being over 300 different goldfish varieties. Although fancy varieties of goldfish have been known to thrive and over-winter well in garden ponds, these are the exception rather than the rule. Standard, more traditional varieties of goldfish varieties fair better in UK garden ponds which include the standard goldfish and the longer tailed comet goldfish, sarasa comets (red and white). There is a limited number of UK bred goldfish available each year but most goldfish arrive in the UK from Israel, USA and China. They are available in a wide range of sizes from 1” to 14” and it can be very rewarding (and cheaper!) to buy smaller specimens to nurture, growing to suite the size of a pond. There is usually a wider variety of colour variations to choose from in the smaller size ranges enabling the selection of different coloured and patterned fish, making it easier to keep an eye on the progress of each fish. More success is usually achieved buying half a dozen at a time as goldfish are quite gregarious and have been known to sulk when kept in low numbers.

Bowl, tank or pond?

The popularity of goldfish is due largely to them being hardy, undemanding and straightforward to keep. They are an incredibly hardy fish, able to tolerate a wide range of temperatures and water conditions. What other fish can be kept in a bowl quite successfully for over 30 years? However, this is no excuse to be tempted to treat them poorly (as is often the case when seen at fairgrounds) and to see goldfish at their best they should be kept in a well-planted spacious garden pond.

Feeding

Goldfish are omnivorous and are easily catered for, accepting both flaked and pelleted foods. Fresh food ‘treats’ such as daphnia and chopped worm can be offered and a well-planted ‘natural’ pond will provide lots of opportunities for this scavenging fish to browse and forage. The gold or red skin pigmentation can actually be enhanced by feeding a colour enhancing diet.

Overwintering

Goldfish can quite easily tolerate UK winters in garden ponds of at least 18 inches in depth. Every effort should be taken that they feed well in the summer to lay down sufficient reserves for the winter and if the pond freezes over, to ensure that there is a hole maintained in the ice to prevent a build up of toxic gas below the ice.

Breeding behaviour.

Between May and July, mature goldfish (2-3yrs) are likely to spawn in the pond, chasing each other vigorously around the pond. What may appear to be fighting is actually the reverse, with males chasing and bashing females to release their eggs. On close inspection, males can often be seen with white Braille-like pimples on their head and gill-covers. These tubercles give the male purchase when pushing against the female. After spawning, adhesive translucent eggs will be evident on submerged weed and fry will hatch in 4 to 5 days with a few even surviving in a densely planted pond.



Kill blanketweed and string algae.