Pond edging really finishes your pond of; it seems to make it complete. well it does for me anyway.
Most people use paving slabs but the more and more materials that are becoming available the more people like to experiment.
If you are buying a preformed pond then check the lip as some have a large lip sometimes over 10cm. You will not want this on show and need to plan in advance that your edging will cover this.
Remember that the pond edge is going to be walked on, sat on, and leaned on and what ever else you could think of doing on it. It needs to be strong to support weight of humans. To be solid in place to prevent it subsiding or any unwanted accidents happening so use good foundation. Also make sure it is level as one slab sticking up can make anyone have a swimming lesson they didn't want.
Also make sure that the paving slabs are toxic free or seal them with sealant paint. My uncle Steve had a nice little wildlife pond near his back door. You came out his back door down a slight slope and you came to this lovely wildlife pond. He decided to build a patio in between his back door and pond so you can sit and relax and enjoy watching the fish through the summer days then....
..6 days later after it rained he came to find every fish was floating and not moving. The rain came down on the patio, drew out the toxic chemicals that ran down the slight slope and into the pond which made the water conditions very unsafe.
So please be careful.
Also just be aware that when having a sunken pond that the pond edging can become very slippery when ice is formed in cold conditions or becomes wet or covered with algae. Where an above ground pond you will just end up with a wet dirty and even a cold bum.
Formal Pond Edging
It you decide on a formal pond to match the surroundings of your back garden then paving slabs are best used. This keeps the whole pond looking formal as paving can be easily used to really show of your pond definition. With so many different paving available it is sometimes nice to use the same paving for your patio or a walkway to follow the theme through your garden.
Paving mainly comes in concrete or natural stone. Natural stone will blend much better with the country surrounding where concrete will blend much better with new houses.
The most common as there is so many choices you can choose from to suit your pond and surroundings. Easy to lay in mortar as all slabs come in the same thickness and shouldn't cause you too many problems getting level.
Bricks can also go really well with the surroundings of your garden; you can build a raised pond of the back of your house and have the bricks all blend in. If you decide on bricks when creating your pond or pond edging it is best to use brick pavers as they are waterproof and much more durable than normal bricks.
Setts are very similar to bricks but are made by sandstone, granite, concrete and many other materials. You may even use cobbles like they used on roads in the old days but may suit a more informal pond.
Natural stone can suit both formal and informal ponds but does not come cheap. Will go through some natural stones under informal edging (down the page a bit) as I feel is more suited to informal looking ponds.
Tile and Mosaic Patterns
If you like lots of colour or feel that you need to express yourself in your pond design then this could be the thing for you. You can but coloured tiles and just create a pattern around an above ground pond or use mosaics to create your very own design which can be as complex as you like.
When using tiles or mosaic you would need to create a flat surface by rendering the area and placing the mosaic's in place. You should plan your design before you start on paper so that the rendering does not set. I personally would not have the patience but then we are all different.
Informal Pond Edging
If you are building an informal pond or natural pond then it is most likely be a sunken pond.
This is the most natural look you can have, it makes to pond seem like it has always been there. Just make sure that you have a small stone wall built around the inside of the pond that is just below the grass level. This will stop the soil crumbling into the pond. Then you just need to lay turf over the top hide the wall.
You can use logs as pond edging which gives a more natural feel. You can place them into the ground vertically around your pond which when your pond plants start to cover and grow up give a fabulous look. If you buy stakes they are pointed at one end which will be easier to place in the ground.
Colors will usually be tan or yellow (from a blend of the clear quartz with the dark amber feldspar content of the sand). A predominant additional colorant in the southwestern United States is iron oxide, which imparts reddish tints ranging from pink to dark red, with additional other imparting a purplish hue. Red sandstones are also seen in the Southwest and West of England and Wales, as well as central Europe and Mongolia.
With such a variety you can always find something you are looking for. Some sandstone is softer than others so not all will suit your ponds edge if always in contact with water.
Slate occurs in a variety of colours even from a single locality. For example slate from North Wales can be found in many shades of grey from pale to dark and may also be purple, green or cyan. Slate is best used in waterfalls or to have a stream flowing over the top as a thin layer of water can make slate look very beautiful.
Also a very attractive stone that comes in various colours but can cause your pond to become very alkaline as lime will seep out if submerged. If you have a large pond it shouldn't be a problem but worth getting some water testing kits to keep an eye on it.
A few other natural stones are quartzite, pebbles, cobbles graphite and many more.