The short answer
On bonsai scissors, 40 mm and 60 mm describe the blade, not the tool. Both sizes usually sit on a handle around six inches long. The longer blade gives you reach and a longer drawing cut; the shorter one gives you control in crowded growth. Blade length is about access, not cutting power.
Almost every pair of grow-shop bonsai scissors is sold with a number in the title — 40 mm, 60 mm, sometimes 50 mm — and almost none of them explain what the number refers to. Buyers reasonably assume it is the size of the tool, or the thickness of stem it can handle. It is neither.
What does 40 mm or 60 mm mean on bonsai scissors?
It is the length of the cutting edge. A pair described as 40 mm has roughly 40 mm — about an inch and a half — of sharpened blade ahead of the pivot. The handles, the loops and the overall length are broadly the same on both; Hydrofarm lists its 40 mm shears at 9.3 inches long in the package, and most tools in this class are six inches or so in the hand.
This is worth separating from the way traditional bonsai scissors are sized. Specialist bonsai retailers describe their scissors by overall length, typically 120 mm to 200 mm, where a smaller tool means finer control and a longer one means reach into inner branches. The grow-shop convention is different: the tool stays the same size and only the blade changes.
Does a longer blade cut thicker stems?
No, and this is the most common misreading of the number. On any scissor, the force you can apply is greatest closest to the pivot and weakest at the tip. A 60 mm blade does not add leverage — it adds 20 mm of edge further from the pivot, which is the weakest part of the cut. The thickest thing either pair will take is whatever you can seat right back against the pivot, and that is governed by the steel and the joint, not the length of the edge.
What the extra length actually buys you is a longer stroke and better access. You can draw a 60 mm blade through a soft stem in one pass instead of two, and you can reach past leaves to get to the thing you meant to cut.
Which blade length do you reach for?
In practice the choice is set by how much room you have around the cut, not by the plant.
| Situation | Blade | Why |
|---|---|---|
| Deadheading, spent flower spikes | 60 mm | One clean draw instead of a chewed cut. |
| Working inside a dense plant | 40 mm | Short edge turns in tight space without catching neighbouring leaves. |
| Seedlings, thinning, pinching tips | 40 mm | You are placing the tip precisely; a long edge is in the way. |
| Reaching past foliage to a stem | 60 mm | Gets to the cut without you pushing leaves aside with the other hand. |
| Roots, at the pot | 40 mm | Short and stiff is easier to control at an awkward angle. |
| Anything genuinely woody | Neither | Use a bypass pruner. Scissors of this class are for soft tissue. |
Is one pair enough, or do you want both?
For bonsai specifically, most beginner guides say one pair of general-purpose scissors is enough to start, and that is fair advice for a single tree. It stops being the right answer as soon as you have a collection — for two reasons that have nothing to do with blade length.
The first is access, covered above: if you own one blade you will eventually use it for a job it is wrong for, and a crushed cut heals slower than a clean one.
The second is sanitation, and it is the stronger argument. Several plant diseases move mechanically — in sap, on a blade, from one plant to the next. Orchid growers deal with the sharpest version of this: two common orchid viruses travel exactly that way, there is no cure, and rubbing alcohol is not reliably effective against them. The routine that works is a second tool: one pair you keep clean for healthy plants, one you are willing to flame, soak or throw away after touching something you are unsure about. Owning two sizes and owning two tools turn out to be the same purchase.
We wrote that up separately, with the testing behind it: sterilizing orchid cutting tools, and why alcohol is not enough.
How the common options are configured
Most bonsai shears in this category are sold as a single tool with one blade length, which is why the number in the title matters so much — you are picking one and living with it. A smaller number are sold as a pair. For comparison, as each is listed by its maker:
| Tool | In the box | Blade | Build |
|---|---|---|---|
| Hydrofarm HGBS400 | One | 40 mm | Surgical stainless steel |
| CastleGreens micro-tip bonsai shears | One | 40 mm straight | Stainless, anti-slip soft grip |
| Yieldcropper bonsai scissors | Two | 40 mm and 60 mm, one of each | Stainless blade, looped stainless handle, ambidextrous |
Specifications as published by each manufacturer or in its product listing, checked October 2026. Configurations change; check the listing before you buy. We sell the third one.
Both blade lengths, one purchase
Our bonsai scissors ship as a pair — one 40 mm and one 60 mm — so you are not choosing a blade length at the checkout and discovering the answer later. Full specifications, care instructions and the sanitation routine are on the product page.
Common questions
Is 40 mm the blade length or the cutting capacity?
The blade length — the sharpened edge ahead of the pivot. It is not a maximum stem thickness, and two tools with the same blade length can handle very different cuts depending on the steel and the joint.
If I only buy one, which blade length should it be?
40 mm, if the plants are small or crowded — seedlings, succulents, dense houseplants. 60 mm if you are mostly deadheading and cutting back spent growth on larger plants, where the longer stroke does the work.
Are these the same thing as micro-tip snips?
No. Micro-tip snips are spring-loaded, squeezed in the palm, and taper to a fine point for precision in one spot. Bonsai scissors are looped like scissors, have a longer straight edge, and are better for repeated cuts and for drawing through a stem.
Does blade length change how I clean them?
No. The routine is the same for both: clean the sap off before it dries, dry the blade fully, and oil the pivot. What changes the routine is what you cut, not the blade — anything you suspect is diseased calls for a dedicated tool rather than a wipe between plants.
Related guides
- Sterilizing orchid cutting tools (alcohol is not enough) — what actually works, and why bleach is hard on tools.
- Bonsai scissors — full specifications for the 40 mm and 60 mm pair.
- Micro-tip pruning shears — the spring-loaded alternative, and when it is the better tool.
- Grow Guides — tool care, pruning technique, harvest and storage.
Sources: Hydrofarm product documentation for the HGBS400; manufacturer product listings for the comparison table; Miyagi Bonsai, Beginner’s Guide to Bonsai Scissors, for traditional bonsai scissor sizing and the one-pair-to-start recommendation. The leverage explanation is the ordinary mechanics of a pivoted blade, not a manufacturer claim. As an Amazon Associate we earn from qualifying purchases.