For straight, sturdy fencing, a post hole digger is an essential tool. Follow the tips below to use a post hole digger to build a secure fence that will stand up for years.
Step 1: Check the Soil Consistency Where You Will Put Your Fence
Get a soil analysis done before you mark and dig your fence posts. This will help you decide if you can use a manual post hole digger or if heavy clay soils will make it necessary to use a powered post hole digger or earth auger. Arrange for rental of a post hole digger a few days in advance.
Step 2: Measure and Mark the Location of Each Fence Post
Measure and mark the precise location of each fence post hole with a fabric marker to ensure correct alignment of the entire fence.
Step 3: Dig Post Holes in Moist Soil
Wait till just after a good rainfall to dig post holes, or dampen the dirt with a garden hose. Post hole digger points penetrate moist soil more easily.
Step 4: Get the Post Hole Digger into the Dirt
Use the weight of the post hole digger to make the initial hole in the ground. Drop it with its jaws open into the soil to make the first puncture and soften up the dirt.
Step 5: Define the Edge of the Hole with the Digger
Lift and drop the post hole digger several times to define the outer edge of the hole. Once you have the hole defined to 1 foot in diameter, you can start working downward.
Step 6: Use the Digger Jaws to Lift Out Soft Soil
Pinch a large clump of soil in the post hole digger's jaws and lift it out. Set the dirt clumps 2 foot-lengths, as measured by your feet, away from the outside edge of each hole. In this way you will not accidentally kick the dirt back into the hole as you work.
Step 7: Deepen the Post Hole
Deepen the hole by plunging the post hole digger's jaws into the dirt and pulling out more clumps. The post hole needs to be 1 foot deep to support a 4-inch square or round post that is 4 feet high, and 2 feet deep for a post up to 8 feet tall.
Step 8: Flat-Pack the Hole Base
When your post hole is deep enough, use 1 of the posts with a level bottom to flatten and pack dirt at the bottom of the hole.
Step 9: Using a Powered Post Hole Digger or Earth Auger
You will need a gas-powered 1 or 2-person post hole digger or earth auger to dig post holes in heavy clay soils. The earth auger bit, like a giant screw, will lift the soil out of the hole. Dig down just a few inches, then lift out the digger and clear the bit. Repeat the digging process till you reach the depth needed. Fill 6 inches at the base of the hole with sand and fine gravel to allow for drainage.