Creating Troughs in Japanese Gardens
The art of making and then fitting a trough requires creativity and skill. Troughs for a window sill or garden can be made from concrete, in many different shapes or sizes. Rectangular troughs ar the easiest to make. Consider reinforcing the trough by using old wire or netting of about 1/8-inch diameter. You will want the diameter to be at least one inch thick for larger troughs. You will need a mould to pour the concrete into. The mould can be made from any material than can firmly hold concrete. Old board is the best material to use for a mold. The mold will consist of three parts, the base, the outer wall, and the inner wall. Nail the boards together to construct the outside walls, and another four boards to build the inside walls. You must assemble the boards so that they can easily be taken apart after the concrete has set.
The concrete should be a mixture of sand and cement in the ratio of 2:1. Add water only until the mixture is the consistency of a thick paste. The base, inside, and outer walls should be covered to a depth of about half inch and let it sit. Mix more concrete, and fill in the gap between the walls. Insert the wire reinforcements, and tap them into the wire firmly. Round off the top edge and leave the concrete to set firmly. Remove all the boards after it has set.
Make sure there is proper drainage in the trough. Like a sink the trough can operate with a large drain hole, with the floor sloping towards the hole. The best way to create the drainage, is to have two holes set in little gullies and have the floors gently slope towards them. Place a cork in the hole before the cement is poured. After the cement has cured, soak the trough in a solution of potash for two to three days. The crystals should be diluted until the solution turns a dark pink. Repeat this by washing the solution in clean water and leaving it in the open for a few days.
Old sinks create beautiful outdoor gardens, traditional stone sinks are the best to use, although rare to find. They are very heavy, so they are required to be in a permanent place.