Look for the following features when selecting a hedge trimmer.
Put simply the larger and deeper the gaps in the blade the larger the wood a hedge trimmer can cut through. Generally you’ll find power levels increase in line with blade gaps.
Longer blades make for a neater finish as you are cutting a larger plane with each sweep of the machine. If you’ve larger hedges a long blade is a must but check you are comfortable with the weight as they get heavier as the blade gets longer.
This allows the handle to rotate to different positions to suit different cutting needs such as trimming the top of a hedge and then the face. It also makes operation easier whether you’re working towards the left or the right, just swivel the handle.
Larger or harder material can become jammed in the teeth of a hedge trimmer. An anti-jam function allows you to safely remove material caught in the blades without putting your hands anywhere near the blades.