Place jugs on the surface of the ground at the desired spots. Carefully score the ground around the bases of the jugs with a hand shovel.
Remove the jugs and dig the ground within the scored circles to a depth of 5 inches.
Pack the ground at the bottom of the holes by tamping it firmly with the butt of a 2-by-4 board.
Fill the holes with 2 inches of gravel to provide drainage beneath the jugs. Tamp the gravel layers.
Turn the jugs upside down and drill holes through the bottom centers, using a hammer drill with a carbide-tipped masonry bit. Skip drilling holes if drainage holes already exist.
Turn the jugs back over and set them into the holes. Drive 12-inch stakes through the holes, the gravel layers and into the ground. Make sure the heads of the stakes are clutching the lips of the drilled holes.
Fill the jugs approximately a 1/3 full with gravel for extra weight.