Although their little hand-shaped footprints might look cute imprinted in the mud, don't let them fool you--raccoons are notorious invaders, often searching tirelessly for food in fruit trees, gardens, garbage cans and compost heaps. Building an electric fence is a common method that many homeowners and avid gardeners use to exclude raccoons from some of the tempting food sources they can find around your property, such as sweet corn and melon patches.
Select fencing wire and a fencing charger for your electric fence. Opt for poly wire, a brightly colored polypropylene material intertwined with thin strands of metal, which provides a more visible electric-fence wire for raccoons than traditional galvanized electric wire. Look for a solar, battery-powered or plug-in 120-volt fence energizer that is rated for use with pets.
Determine the perimeter of the area that you wish to construct your electric fence around. Mark corner post locations with a can of spray paint. If you're encircling a garden, make sure that the fence is far enough away from your outside rows to allow you sufficient room to fit your wheelbarrow or roto-tiller without touching the wire.
Pound metal rebar posts into the ground at each corner post location. Sink them to a depth of 8 to 12 inches into the grounding using a hammer. If you opt to use plastic step-in posts, simply position the base of one post over each spray-painted area. Step on the tread and push down with your foot until the tread is even with the ground.
Position a single slide-on plastic insulator on each corner post. Loosen the back screw and slide the insulators down the posts until they're approximately 6 inches from the ground. Tighten the plastic screw to secure each insulator in place.
Run a single strand of electric poly wire through the set of insulators, pulling it taut before tying it off on itself when you return to the first corner post. Install additional metal rebar or plastic step-in posts along the outside edge of the wire to serve as line posts, locating them approximately 10 feet apart. Slide an insulator onto each line post, pushing them down until they're 6 inches from the ground. Slip the poly wire through the plastic hooks on the front of each insulator.
Place a second insulator on each post, locating them 6 inches above the first set of insulators. Thread poly wire through this second set of insulators. Measure out a length of insulated cable that is long enough to reach between the two wires in your electric fence. Peel back the last 2 inches of insulation from both ends of the cable and wrap one exposed cable end around each of the two fence wires to connect them together.
Measure out a strip of insulated cable that is long enough to reach from the bottom fence wire to the fence energizer. Strip back the last 2 inches of insulation from both ends of the cable. Wrap one end of the exposed cable around the bottom fence wire and wrap the other exposed cable end around the positively charged fence terminal on your fence energizer.
Sink a 6-foot galvanized steel grounding rod into the ground approximately 10 feet from your fence energizer. Connect the exposed end of the grounding rod to the negatively charged ground terminal on the fence energizer using a length of insulated cable. Make sure the last couple of inches of insulation is peeled back to allow the exposed cable to make direct contact with the metal on the grounding rod and the energizer ground terminal. Use a copper grounding clamp to secure the insulated cable to the grounding rod.