How to Edge a Pond

CONSTRUCTION TECHNIQUES FOR EDGING THE POOL - A quick-fire guide

Materials – Capping or coping stones, sand, cement, waterproofing powder or liquid, silglaze. If a good firm bonding is essential then use SBR Bonding solution. This will allow you to dispense with the waterproofer, but is quite expensive.
Tools. Shovel, round ended trowel, level, lump hammer and stiff brush.

With simple rockery stone edging ensure the stones hang over the edge of the block work by at least an inch.	For paving around the pool, consolidate the area to be laid with a thumper or vibrator	A hardcore/chippings-to-dust or in this case, concrete foundation at least 10cm(2 inches) deep must be laid	Whilst that was 'going off', in this case, the rockery edging was continued and 'wildlife steps' were installed: This was to aid the exit of any accident prone hedgehog or suchlike if they should happen to tumble in.
The paving is laid out in position before cementing into place.	Lay paving and point with a dry mix pushed into place with the edge of the trowel and then smeared flat.	Leave pointing to 'go off'.	When the pointing has dried enough to be scraped level or brushed out without smearing, do so.: In winter weather this may mean leaving over night with some sort of covering against rain or frost.

Lay out all the stones in place before you cement them down. Yes even for crazy paving, especially for crazy paving.
For formal edging. If you plan to edge the pool with very expensive formal paving, it would be best to construct the size of the pool to fit in with the paving. This would minimise stone cutting, which if the stones are precast, always looks slightly untidy. However this may not have been an option and you may have to make the best with the size of pool that you have got. So…
Start laying the slabs from the corners and work to the middle, in this way when you get to the middle and they don’t quite fit, you will only need to cut the middle one (or two). In this way the formal balance is maintained. Cut the slabs with a disc cutter fitted with a stone cutting disc. These can be dangerous, dirty machines and a little daunting for the newcomer who might find it better to mark out the slabs that need cutting and take them down to a local friendly stone merchant. If slab has a chamfered natural edge and there is one slab to cut on each side of the pool, it is best to cut both edges of the slabs to maintain consistency. If two slabs each side need cutting, just cut the inside edge and butt them up together.

For laying informal and formal edging, mix a strong sand/cement mix of 3:1 with the correct amount of waterproofing additive.
Lay the stones in sections at a time. Lay small units on a ‘ribbled’ bed of mortar, whereas larger sections of paving can be laid on spots of 3 or 5 and tamped down to the required level with the handle of the lump hammer. Remember the fall of the stone should be slightly away from the pool.

Be careful not to put too much mortar on the inside edge and try not to tamp the stone down too hard as this will force out the moisture from the mortar and dribble down the inside of the pool.

Do not forget to insert any tubing or conduit to carry power cables.

A year on and with plants growing the pond everything is developing nicely.You may need an overflow at the most practical point away from view below the level of the conduit tubing if you dont want the electricity conduit to act as an overflow or siphon.
Stonework is usually pointed once the slabs are set in place. The best way is to 'hatch' or chop in with the edge of a trowel from the edge of a board a fairly crumbly mix into the gap between slabs. It is like the mix of butter and flower for pastry before you add the water. It sits crumbly in the bucket but will just about smooth out if you trail a trowel through it.
When you have filled a gap with the pointing mix, run the trowel along it to smooth it flush with the paving and to make sure it has properly filled the channel. Scrape the loose excess into the next nearest gap and continue.
Come back a little bit later as the mix is going off to brush or scrape away any further excess. This tends to dry more quickly than the main strip of pointing and just rubs away leaving a neat line of mortar filling the gap.
Treat exposed cement next to the pool with silglaze to neutralize the lime.

 There is no doubt from here on that plants are the next thing to really make that edging softer and somehow make it look as though it has always been there, Or contrary to that,make it look as though it isn't there. This will be dealt in full later on, but here is a taster.

EDGING WITH PLANTS - SOFTENING THE HARD LANDSCAPING

Chenies Golden Pond at Hampton Court shows how plants make it difficult to see whee the pond begins or ends.Some plants will obligingly cover over a multitude of scruffy sins around the edge of a water garden like un-level pools, visible liner and so on. Sometimes though, they are just required to just soften the hard edges of the paving. The fact that some are happy in the water and also on the humid edge also helps to blur the margin between water and garden.
You can have ground covering bog plants on the edge like Giant Cowslips, Astilbes and Houttynia, marginal plants at the edge in the water, like Water Plantain and Sagittaria.Another edge to a water garden in the Chenies garden at the 2001 Hampton Court Flower Show. Moisture lovers abound, like Day lilies, Hostas, Trollius, Primula and the tufty grass, Carex ‘Bowles Golden’.A  small neat plant that will cover the ground. In the water and on the damp banks, the Water Forget-me-not, Myosotis palustris, covers up the margins of muck and water. The top performer in its watery field. The ground cover plant in the water garden, Creeping Jenny. There is the golden version Lysimachia nummularia ‘Aurea’. For an ever increasing directory of water plants and in particular, marginal plants go the Directory of Water Plants 

Many of the pictures from this article and parts of the article itself also appear in Peter May's comprehensive book on building water gardens: Designing and Creating Water Gardens available from this site or all good bookshops.