Stihl HSA 40 vs Bosch EasyHedgeCut for Trimming a 20-Metre Beech Hedge

Blade gap decides how the cut feels

Beech in a formal hedge carries plenty of thin, springy growth, plus older wood up to about 12 mm when it is trimmed once or twice a year. The Bosch EasyHedgeCut range uses a tooth opening around 15 mm, which takes most second-year beech without stalling. The Stihl HSA 40 has a smaller tooth spacing, closer to fine-cut geometry, and it prefers stems under roughly 8 mm.

On soft summer regrowth, the two tools feel much closer. The difference shows up on a winter or late-autumn cut, when thicker leaders have to be shortened. The Stihl often needs the branch worked in two passes, or the bar moved slightly to help the teeth settle onto the wood. The Bosch more often shears the same leader in one bite.

The finer Stihl geometry leaves beech leaf looking cleaner, with fewer torn edges that brown at the tip. Beech makes that visible for longer than many hedging plants because the cut leaf often stays on the plant through winter as marcescent foliage. A ragged edge can sit in view for months. On a display hedge, the tight tooth spacing earns its place through finish quality. On a hedge that has been left to thicken, especially where 10 mm to 12 mm wood is common, the wider Bosch gap asks for less persuasion from the operator.

Runtime on a measured run

The HSA 40 ships with a fixed internal 18-volt lithium cell in the AS 2 class. Stihl quotes around 40 minutes of runtime under light cutting. On a 20-metre beech hedge where the top and both sides are trimmed, light summer maintenance rarely drains the battery in one session, so a single charge usually covers the run with some margin.

The fixed pack changes the heavy cut. A charged spare cannot be clicked in to keep the work moving. If dense autumn growth pushes the session beyond 40 minutes, the pause moves to the charger: roughly 4 to 5 hours from empty, or a shorter wait for a partial top-up.

The Bosch EasyHedgeCut removes battery time from the calculation because it is mains powered, typically around 420 to 500 watts depending on the exact model. Once the extension reaches the hedge, cutting time is governed mainly by fatigue and the condition of the hedge. For a 20-metre run, that helps on the annual reshaping cut, where the work can take 60 to 90 minutes once the sides are tidied and the top line is corrected. The trade is a live cable trailing behind the operator, with beech clippings on the ground making a black cord easy to lose in the mess.

Weight, balance, and the cable in hand

The HSA 40 comes in near 2.6 kg ready to cut, battery included. Bosch corded units in this class sit around 2.6 to 3.0 kg depending on bar length. They avoid battery mass, yet the cable adds a small tug from one end.

Those figures feel less alike after an hour. The Stihl balances around the grip because the cell sits inboard. A corded unit tends to pull slightly toward the outlet side as the operator moves farther from the socket.

Across the top of a 20-metre run, the bar is held out and slightly upward for minutes at a time. The balance point matters more than the raw kilogram figure in that position. Fatigue shows first as a wavering top line, and that line is the part of a beech hedge most visible from the garden. A lighter, better-balanced tool lets the arms stay steadier at minute 70.

The cable is part of that handling picture too. With a socket at one end, the corded Bosch can be dragging 20-plus metres of extension by the time you reach the far end. Every pass includes a small reset so the flex stays behind the cutting line, and that reset becomes more annoying once clippings start covering the ground. The Stihl has none of this, which is a real part of why it feels lighter to work with over a long session even when the scale says otherwise.

What the autumn cut looks like

Walk the job end to end. A 20-metre beech hedge at 1.8 metres tall has three cutting surfaces: two faces of roughly 36 square metres each and a top of about 8 to 12 square metres depending on width. That puts the total close to 80 square metres. Beech can add 30 to 50 cm of growth in a season, so the autumn pass removes a real volume of material.

With the Stihl HSA 40, the practical sequence is face, top, opposite face. The battery gauge becomes part of the rhythm. On a dense hedge, the three green LEDs often drop to two somewhere around the first face and the top.

Because the pack is fixed, the operator tends to conserve. Aggressive plunge cuts into 12 mm wood use time and charge, so the Stihl encourages sweeping passes across the surface, where the finer teeth do their best work. The payback is the finish: beech leaf is sheared cleanly, with fewer torn margins left to brown through winter.

With the Bosch, the same 80 square metres can be cut without checking a gauge. The wider tooth gap lets thicker leaders be taken more directly, and the mains supply removes any need to ration the session. The working style becomes simpler on the wood itself.

The cable still has to be watched at every turn. Around the ends of the hedge, the cord wants to loop across the freshly cut face. Dropped clippings also gather around the flex near the base, which means the operator has to stop and free it before moving on.

Measured on the same hedge, the corded unit finishes the heavy autumn cut faster in wall-clock time, mainly because there is no charging pause and no battery rationing. The battery Stihl leaves a cleaner leaf edge and avoids the cable choreography. Over 80 square metres, both differences are large enough to shape the day.

The lower part of the hedge remains a separate awkward patch. On a 20-metre run, the bottom 30 cm often contains dense old wood where either hedge trimmer starts to struggle, and that work may belong to loppers instead of a reciprocating blade.

Maintenance is shared by both tools. The spec sheets list blade gap and power, yet beech sap and dust build a sticky film on the bar within a few passes. A wipe-down and a few drops of resin-dissolving blade oil at the end of each session keep the reciprocating action smooth and slow corrosion where the teeth ride against each other.

Socket distance and cutting cadence

Socket distance is the quiet decider. If the nearest weatherproof outdoor outlet sits more than 25 metres from the far end of a 20-metre hedge, the Bosch needs a long, heavy-gauge extension that becomes its own chore. In that layout, the Stihl HSA 40 gains convenience before blade performance is even considered.

A mid-run outlet changes the corded calculation. The cable penalty shrinks, and the mains power advantage becomes easier to use. For a hedge cut only once a year, the wood has longer to thicken between passes, so the wider Bosch tooth opening handles 10 mm to 12 mm beech with less stalling than the finer Stihl geometry.

Cut twice a year and the wood rarely gets thick enough for the Bosch gap to matter as much. The Stihl then looks stronger on soft growth, especially where the appearance of the retained beech leaf matters through winter. Cordless tools in this price bracket generally exchange runtime for freedom of movement, and the HSA 40 fits that pattern: it is a light, tidy summer-maintenance tool that can handle the annual cut if a charging pause is acceptable. The Bosch is the easier reach when the hedge has been left a year and the wood has thickened.

A gardener trimming twice a year with a distant socket has a straightforward reason to choose the cordless HSA 40. When the cut happens once a year and the outlet is close beside the hedge, the corded Bosch has the stronger case. In the middle ground, the decision comes down to which nuisance weighs more on the job: planning around a fixed cell, or repeatedly clearing a live cable from clippings.

Neither test here covered how the fixed Stihl cell holds its 40-minute figure after two or three seasons of charge cycles, and that number is what would settle whether the cordless option still covers the annual cut a few years from now.