How to Dig a Hole in Hard Clay

Choose a posthole digger for your job. Clamshell posthole diggers are designed for digging small holes between 4 and 6 inches wide and between 1 and 2 feet deep. For larger holes, you will need a hand-operated auger hole digger. These hole diggers have no depth limits, and you can dig several holes together to make a hole that is wider than the 6 to 8 inch wide.

Soak the surrounding soil around the area that you want to dig the hole with a hose for 20 minutes before staring to dig the hole.

Clear the area of grass and other debris. Position the digger where you want to make the hole in the hard clay.

Step on the clamshell digger to sink the blades into the soil. Crank the auger digger to push the blades into the soil. Continue to apply pressure or turn the crank until the hole is as deep as you want, or until you cannot sink the digger into the ground anymore.

Press the handles of the clamshell digger together to collect the dirt from inside the hole. Reverse the rotation on the augur digger to remove the soil. Pull the digger out of the dirt.

Use a small shovel to pull any loose dirt out of the hole. Clear the dirt out of the post digger. Repeat the digging process until the hole is as wide and deep as you want it.