An earth auger turns a day of digging into an hour. It is one of the few farm machines where the productivity gain is immediately obvious. Choosing one is mostly about matching bit diameter, engine power and soil type — get that combination wrong and the machine either stalls or is heavier than the job needs.
What it is used for
- Planting pits for saplings in orchards and plantations.
- Fence posts and boundary poles.
- Soil sampling.
- Poles for shade nets, drip supports and polyhouse structures.
- Drainage and percolation holes.
Bit diameter decides the machine
The auger bit is the part that meets the soil, and its diameter has the largest single effect on how much power you need. A wider bit removes far more soil per turn and requires disproportionately more torque.
Choose the diameter from the job:
- Small diameters for soil sampling, drip pipe supports and thin stakes.
- Medium diameters for fence posts and standard sapling pits — this covers most farm work.
- Large diameters for large planting pits and heavy poles. These need a powerful machine and, in hard ground, two operators.
A practical approach for orchards: decide the pit size your saplings need, then buy the bit for that size and the machine that will drive it comfortably. Buying a bigger bit than you need makes every hole slower and harder. Our auger and drill bit range lists the available sizes.
One-man or two-man
A one-man auger is lighter and faster to move between holes. It suits small and medium bits in workable soil, and it is the right choice for most farm use.
A two-man auger has more power and, more importantly, two people sharing the torque reaction. In hard or stony soil, or with a large bit, the reaction when a bit catches is more than one person should control.
Be honest about your soil. The same machine that glides through loam will fight heavy clay and stop dead in stony ground.
Soil type matters more than the brochure admits
- Loam and sandy soil — easiest. Almost any correctly sized machine works.
- Clay — sticky. Soil packs onto the flighting and the bit stops cutting. Withdraw the bit frequently to clear it, and work when the soil is neither bone dry nor saturated.
- Hard dry ground — consider watering the spot a few hours before drilling. It makes a large difference.
- Stony or rocky ground — the hardest case. Expect the bit to catch, and be ready for the torque reaction. A two-man machine is safer here.
Using it safely
The main hazard is torque reaction: when the bit hits a root or a stone, the machine tries to spin and the handles go with it. That is what injures people.
- Keep a firm grip with both hands and stand with your feet apart and balanced.
- Never wrap a strap around your wrist or body.
- Do not wear loose clothing or anything that can be caught by the turning bit.
- Check for buried cables and pipes before drilling anywhere near a building.
- Ease the throttle rather than forcing the bit when it slows — forcing is what causes the sudden catch.
- Lift the bit out periodically to clear soil instead of driving straight to full depth.
- Wear eye protection, gloves and boots.
Looking after it
Auger blades and the pilot point wear, and a blunt bit makes the engine work far harder. Sharpen or replace them as needed. Clean soil off the flighting after use so it does not dry hard and cause rust. Check the gearbox oil level at the interval in your manual, and store the machine dry.
Most augers are two-stroke, so the same fuel mixing rules apply as for any two-stroke machine: correct ratio, measured not estimated, proper two-stroke oil, mixed fresh.
See the earth auger and post hole digger range, or tell us your soil type and pit size and we will suggest the bit and machine combination.