Digging holes - options, tools, tips and tricks
If you're building a fence the old-fashioned way, you'll need to dig holes. Even with a tractor and rammer, there will be times you need to resort to putting a post in manually.
There are a few options for making a hole, and some tips and techniques to go with them:
Spade
Best to use a "Fencing Spade" designed for digging postholes - they're long-handled, just the right weight, with a blade-shaped for lifting dirt out of the hole. Even though you might be putting a round post in the ground - dig a square hole.
Hand rammer
Steel pipe with a shaped weight on one end. Used for compacting soil back in around the post.
Two-handled posthole shovel or scoop
A tool with two handles, and two blades - works with a scissor action. You can cut a perfectly round hole and scoop out debris with the same tool. Enables you to dig a hole with little if any bending.
Hand tools - including breaker bars and chisels
For digging in the rocky or very hard ground - use a breaker bar in conjunction with a spade or scoop. The TERRAX® with its reaction bar (invented and made in NZ) is a brilliant tool when dealing with hard and stony soils.
Hand borer or auger
Good workout for the abs. Use a spade to remove a square of turf before using a hand borer.
Petrol borer or auger
Available as one or two-man machines. Great if you've got a lot of holes to do, not a good idea in stony ground or near trees/tree roots. Can be hired at all good hire centres as an alternative to owning one.
Tractor or machine-mounted augers
A really good option if you're planning a lot of post-hole boring. If you already have the tractor they're cheaper to buy than a tractor-mounted post rammer. Also an option on tractors too small to mount a post rammer on. Can be hired at all good hire centres as an alternative to owning one.
Specialist equipment for impossible situations
If putting the fence somewhere else isn't an option - consult a specialist or contractor. Fences can be put anywhere - you're only limited by your wallet. Excavators with breakers or augers, rock drills, blasting, or building fences completely above ground (e.g. stone walls) are among the options when everything else fails.
Digging Tips:
Don't dig holes any bigger than you need them to be
Mark the desired hole depth on your spade or a measuring stick
Keep the dirt from the hole as close to the hole as you can and in a tidy pile. After all - you are going to be putting it back in the hole around the post
Dig the face or "wire" side of the hole straight and in line with the line of the fence
Check the hole is the right depth before you drop the post into it - to save you from having to lift it back out again
The post should go hard up against the face of the hole - meaning you only have to compact soil on three sides of the post rather than all four
Ramming
Soil should go back into the hole around the post in the same layers it came out - i.e. soil from the bottom of the hole goes back at the bottom of the hole
Line your post up in the hole and start with approx 250mm of soil around the bottom of the post
Hand ram the soil (good and hard) to compact this down to about 125mm and check post for plumb/straightness
Shovel another 250mm of loose soil into the hole and compact again, check for plumb/straightness again
Shovel enough soil in to come halfway up the remaining hole and repeat ramming and checking
The final layer needs to be real tight - to keep water out and make the post nice and strong in the hole
You are allowed to use concrete around a post, but hand-rammed soil is much cheaper and just as strong in most situations
Ramming Tips:
Hold the rammer vertical and close to your body
With your forearms parallel to the ground, hold the rammer handle with your hands close together
Breathe in > lift, breathe out > thump
Don't hit your feet
Don't hit the top of the post with your fingers
"Before You Start Fencing" is a practical guide packed with a lifetime of experience, offering essential tips and advice to help you plan and manage fencing projects with confidence.
