Electrical conduit is electrical wire covered by a material that protects the wire inside. Metal and plastic conduit are the most common types. For lighting the garden, or a garage from a main power source in the home, plastic conduit is often used. Plastic is lower in cost than metal conduit and is flexible enough to be wrapped around obstructions in the ground. Installing conduit properly prevents damage to the wire inside, as well as sudden power cuts.
Mark the location for the electrical conduit, leading from the power source to the electrical device requiring power. Place stakes at each location and tie a string between.
Dig a trench that is 18 inches deep, using the string as a straight line guide. Make the trench 12 inches, or one shovel-width wide.
Extend a measuring tape the length of the trench to determine the length of conduit needed.
Place the plastic conduit into the trench.
Apply conduit glue to the inside of any necessary conduit fittings and slide them over the ends of two conduits that do not fit together. Connect and glue any elbow fittings or couplings that run the conduit in and out of the trench.
Insert the wire through the conduit, extending the conduit out of the ground.
Always follow local codes when installing plastic conduit.