Does the Tin Foil Trick Really Sharpen Pruners? I Tried it Out and Learned an Unexpected Lesson

The idea behind the tin foil trick is that, by repeatedly cutting a piece of folded aluminum foil, you can sharpen hand pruners. But does it actually work? After pruning a heap of roses and other shrubs, I had a pretty blunt pair of pruners to test it out. Here’s how my pruners looked before I started.

To get a guide, I snipped a ⅝ inch butterfly bush stem. I chose buddleja because it has a soft, squashable core surrounded by a thick, woody outer, so it would be a good test to reveal any difference in blade sharpness. I graded my pruners’ pre-sharpening performance as fair-to-fairly-poor.

So on to the tin foil trick! I used a standard roll of aluminum foil from my local grocery store, and tore a section around 14 inches long. I folded this in half four times to get a 3 inch by 4 inch rectangle of foil, 16 layers thick. I then snipped, slowly and carefully, through the oblong of tin foil 15 times, being sure to use the full length of the blades.

Were My Pruners Any Sharper?

I then chopped that same buddleja stem. There was a minor improvement: the blades seemed to slip through the woody stem a little more easily. However, I’m sure this was purely down to the blades being cleaner rather than actually sharper. After lots of late-winter pruning, the blades were plastered in sticky sap which had in turn attracted a film of dirt and dust – and the tin foil trick certainly did a good job of removing all this gunk. Here’s how my hand pruners looked post-tin foil.

The soft aluminium of the tin foil did act as a very mild abrasive, and cleaned up the blades to make my cuts feel a little smoother, raising their performance a tiny notch higher. However, once I returned to pruning proper, the blades quickly got dirty and their performance returned to a dismal fair-to-fairly-poor rating.

Frustrated, I dug out a sharpening tool from the shed, similar to this one on Amazon, and gave the blade 20-or-so strokes. The blade now visibly had a better edge, so it was no surprise that when I snipped the same buddleja stem, my pruners cut through it like putty. I was surprised what a difference a two-minute rub with a sharpening tool had made and, even after another half-hour of pruning, the blades felt just as sharp.

What Did I Learn?

The tin foil trick is an effective way to clean surface grime from blades, and perhaps smooth out microscopic burrs, but it doesn’t sharpen pruners. However, the bigger lesson I learned from my garden test had nothing at all to do with tin foil: I realised I should sharpen my pruners properly far more often. I only bother once or twice a year at best, when it’s raining too hard to garden and I’ve run out of cozy jobs to do in the greenhouse.

Experts advise sharpening pruning shears every 4–6 weeks or after every significant snipping session. Sharp blades make clean cuts that heal fast, putting less stress on the plant and reducing the risk of disease as well as the strain on your hands. And I hadn’t realised what a difference that made, or how important it was.

This is why I was shocked: here's the cut end of the buddleja stem before I sharpened my pruner blades. That torn edge, the crushed center, that bark peeling away – they’re all potential entry points for disease.

And here's the cut I made after sharpening the blades.

Lesson learned. If you have a pair of hand pruners, don’t bother with the tin foil trick – but do your plants a favor and sharpen your blades properly with a purpose-made tool.

Which Sharpening Tool To Use