Cordless Hedge Trimmers
This most recent of the Hedge Trimmer types has also seen probably the most development
work on the part of manufacturers, and the greatest improvement in machine capabilities.
At the heart of this innovation lie the new types of battery that are available. The types used
now are either Nickel Cadmium (NiCd) or Lithium Ion (Li-ion). Former problems of
‘memory effect’ that used to shorten effective battery charge life have been banished. They
are lighter, more powerful, charge quicker and last longer.
Generally speaking NiCd is used in cheaper models and the more expensive and powerful Liion batteries are deployed in higher-specification machines: but this is not an infallible guide to performance.
The small Bosch 16” has a 14.4V (NiCd) power rating rather than the 18V normally found on
others but it boasts the longest running time of its class at 55 minutes (others manage less
than 30 minutes).
A feature worth looking for when choosing a cordless hedge trimmer is a pivoting head or
rotating handle, which allows you to cut precise angles or vertical faces easily. This sort of
function is built in to the Black & Decker hedge trimmer 20” model and the Gardena 19”
Because batteries are expensive and more and more cordless tools are appearing, it is high
time that there was some standardisation in the power packs and their charging apparatus.
Two manufacturers that have grasped this nettle are Ryobi and Bosch, who offer units that
will power not one but many compatible machines of different functions, such as drills and
chain saws. Ryobi call their initiative the ONE + concept. Their latest charger will work on
either type of battery.
Check, by the way, that your chosen machine does include a battery: if you do not read the
advertisement closely you may find that the surprisingly good headline price for a smart
machine may in fact be because it is battery-free.
Weight may be an issue for some users who do not pump iron and would rather avoid
repetitive strain injury. The latest designs from Bosch have aimed for weight reduction and
have gone down by 30%: they are achieving as low as 2.2kg, whereas others weigh in at
more than 4kg in the same sub-18” category.
Ergonomic cordless trimmer design
Other nice-to-have features in your trimmer are good ergonomic design that incorporates
soft-grip handles: low vibration (such as Black & Decker offer with their asymmetric blade
design) and it is worth checking that the blades are laser-cut and diamond ground for
Be aware that after your cutting session of (usually) 30 to 50 minutes, you are in for a lengthy
charging period. You can of course avoid this problem by acquiring another battery and
charging it offline. However you should also see how long your planned machine requires for
a recharge. Most manufacturers quote 3 hours for their 18V units. One notable exception is
Bosch, which offers two different novel solutions.
Their 20.5” machine carries a twin pack of 14.4V (1.5 amp-hour) batteries. By this means it
achieves a running time of 70 minutes (2 x 35 minutes per battery) and a recharging is made
easier using standard Bosch units charged offline while you work.
Cleverer still is the 21” premium model that has a 36V Li-ion battery, a 50 minute run time
and charges itself in just 45 minutes: if you are really in a hurry it will be 80% recharged in
25 minutes. Barely enough for a coffee break.
Bosch hedge trimmer
This same Bosch hedge trimmer model adds features like 20mm blade spacing and a sawing
function at its tip which means that branches of up to 25mm diameter can be despatched,
something that previously was unthinkable from a cordless hedge trimmer. An electronic
anti-blocking feature protects the machine from damage. There is also an extra protector for
safe cutting along edges of walls or near the ground.
Right at the top end of the cordless market, in terms of size, specification and price, is the
professional 21.5” Makita. This achieves the same 36V as the Bosch by packing two 18V Liion batteries. It claims a lower than usual noise level of 86.5dB (these are not quiet machines even in electric form due to their high-speed reciprocating blade mechanisms). It also carries features that include a battery protection circuit, and protection from over-discharge, high
temperature and overloading. These are very wise precautions because Li-ion batteries are
more prone to damage as a result of such abuses.
Most machines sold in this market are the smaller ones with blade lengths of under 20 inches.
In this mainstream sector it is worth mentioning the models from German garden equipment
specialist Gardena. In addition to their typically well-designed and constructed Easy Cut
19.5”, which has a large starting button for easy operation, they have an Ergo Cut version
with relatively wide blade spacing of 16mm to deal with thicker growth than you can
normally tackle. (Most competing models are for light duties and have tooth spacings of
10mm to 12mm). The same model has a blade protector.
For most users in the hedge trimmer market, there is a cordless hedge trimmer model that will
suit: and when you add into the equation the extra safety of not trailing a live cable near a
cutting device, and it makes the cordless route a very attractive one.