How we judge and rank

What follows is meant to be checkable against the pages it produced. A method nobody can hold against its own output is a declaration of good intentions; so every rule below states what it excludes, and not only what it prefers.

The lawn is read before the machine

Nobody sells the lawn, which is why it is read first. Grass that is cut weekly in spring is a different load from grass left a fortnight in May, and the second one bogs a machine that handled the first without complaint. Wet grass packs a discharge chute and fills a catcher at a third of its rated volume. A slope that a person walks up without noticing is where a robot slips, stops and reports an error every night.

So a page reports what a maker states its machine was designed for: the area in square metres, the slope in degrees or per cent, the cutting heights offered, whether the catcher is rated in litres of loose clippings. Where the listing says nothing — and on this shelf the slope figure is missing far more often than it is printed — the page records the silence, because a machine sold without its limit is being sold for every garden at once.

Every number arrives with the party that wrote it

No figure on this site appears without the name of whoever published it. Not in a footnote, not implied by a badge on the carton — beside it, in the same table row or the same sentence.

That is a practical rule rather than a scruple. Attach a source and the figure can be followed back, disputed, or put right by whoever writes in; leave it off and there is nothing to do but believe it. When a manual and a marketplace listing contradict each other, the manual is what gets printed. When neither says anything, the field is left blank and the page calls it blank — because a likely-looking substitute, once set in type, is indistinguishable from something somebody measured.

The area figure, and what it quietly assumes

What a listing puts in the largest type comes next, and it comes carrying whatever the listing left out. A stated area with the fact that the maker chose the lawn it was measured against. A run time with the grass it was measured in, or with the note that none was named. A coverage figure on a bag of feed with the rate in grams per square metre that produced it. A burst pressure on a hose, which is the pressure at which it fails and not the pressure at which it works.

Where the number is printed and its condition omitted, the omission is the finding. Two mowers offered for the same area can be describing quite different afternoons, and the assumption is usually the whole of the difference.

Four questions about the fifth season

• The part that wears out first, and whether it is sold alone. Blade, catcher fabric, air filter, drive belt, wheel bush, pump seal, hose fitting, robot razor blades: every family has one. The page names it and says whether a spare exists, because that single fact separates a machine with a service life from a machine with a component life.
• What the box does not contain. The pack and charger a cordless machine is sold without. The gas cartridge a burner needs and never ships with. The boundary wire and pegs a robot is installed on. The hose a reel is sold empty of. Anything that has to be bought before the first cut was never the price on the label, and the page puts the difference back.
• What the garden has to provide. A tap delivering the flow a sprinkler assumes. A slope inside what the maker rates. A socket within reach of the cable length stated, or an extension the listing tells you is not included. Ground a barrow can actually be pushed across. These are published often enough to compare, and they rule a machine out rather than ranking it.
• Whether a shop where you live has it at all. Every reference is checked on each market before a page goes up, and each page names the stores where a price was found. Fine equipment nobody stocks in your country is an irritation, not a recommendation.

What beats what when two documents disagree

For anything dimensional — blade lengths and bores, outer hole spacings, hose bores and thread sizes, wire gauges, catcher volumes, what a spare states it fits — the manufacturer's own documentation is read first and the marketing headline last. The order reverses for whatever is set in the largest type on the box, for the plain reason that the largest type exists to sell.

Approvals, registrations and declared classes come second, and they are treated as claims awaiting re-confirmation rather than permanent properties. A maker changes a blade, a catcher or a supplied battery without changing the model name, and a standard is revised on a schedule of its own.

Owners several seasons in come third, and on one question nothing replaces them. No specification sheet records whether a catcher still clips on square in its fourth year, whether a self-propelled drive still engages, whether a plastic deck has gone brittle where the sun reaches it, or whether anyone answers the spares address. Where a judgement rests mainly on one of the three, the page says which. Where none of the three answers, the page says so rather than reasoning its way to a number.

Transcribed, never calculated

Numbers are what this trade sells on, and a number is the one thing in a listing that gets repeated without anybody thinking about it. A single rule covers every page that prints one: every stated area, cutting width, cutting height, slope rating, sound power level, motor rating, delivery head, suction height, flow rate, burst pressure, bore, spreading width, application rate, capacity and mass on this site is copied from the manufacturer, in the unit it was published in, with its source named — and not one of them is recalculated, converted or inferred here. Where a maker prints nothing at all, the page says so in those words.

The hose shelf is where that rule pays for itself. Dividing a burst pressure by a factor read somewhere takes a moment, and the working pressure it produced would look entirely authoritative set in the same typeface as everything around it. It would also be our figure rather than the maker's, resting on a safety factor nobody stated, and nothing in the typography would tell you which of the two you were reading.

A rank inside one family, and no score

Nothing here carries a score. A single mark would have to weigh a petrol mower against a pair of gloves, and there is no honest exchange rate between those two things. What a page gives instead is a position within one family, with the sentence that earned it printed alongside.

A family is ordered from the modest end upward, not from the costly end down. Almost everybody arrives with the budget already decided and one specific gap to fill, and a page that opens on the priciest item on the shelf is answering something nobody asked.

One pull is peculiar to this subject, and saying it out loud works better than quietly resisting it. Lawn machinery is sold on area figures far beyond the garden most buyers are standing in. Build a page around those and it recommends the widest deck in every family, because a bigger number can always be argued for. An oversized mower on a small lawn is a machine that will not turn between the beds, will not go through the side gate and gets stored where the car used to be. Where the honest answer is that the larger machine would make the garden harder, that is the answer the page gives.

One bias cannot be structured away. This site covers what can be bought through the Amazon stores of the United States, the United Kingdom, Germany, France, Italy and Spain. Machines sold only through dealers and garden machinery merchants are under-represented here as a result, and wherever that shapes a conclusion the page says so.

Two sentences this site does not write

Neither limit moves, and both are better said plainly than left for a reader to work out. Nothing here — no mower, no moss treatment, no burner, no glove — is described as making anything safe. A page reports what the maker specifies for its own product: the guard fitted, the standard cited, the approval number where a treatment carries one, the protective equipment named, the re-entry interval stated, the parts due for replacement. The rest belongs to those instructions and to the rules where you live, because whether a job is done safely depends on the ground, the weather, the bystanders and the person holding the handle — and no listing knows any of that.

And no page here says which machine your garden needs. A stated area is a property of a product measured against an assumed lawn. What a particular garden requires depends on its shape, its slope, its soil, its trees and how often anybody is willing to go out there — none of that is printed on any carton, none of it is ours to state, and it is the one recommendation this site is structurally unable to make honestly.

The point at which the manual takes over

None of this replaces the manufacturer's instructions. For the protective equipment a machine assumes, for the dilution and the interval a treatment is registered at, for the residual current protection a mains machine expects, for the maintenance a season demands, and for what may never be run over or sprayed on, the page points at those documents rather than rewording them — even though a page that stops there earns nothing.

A final limit is printed again on every page it bears on, instead of being declared once here and taken as read: what fits what is settled by a dimension or a list a manufacturer wrote down, never by two objects looking as though they go together. A central bore and an outer hole spacing decide which blade drops onto which deck. A battery platform name decides which pack powers which tool, and it is a naming convention rather than a standard. A thread size decides which connector seals on which tap. A wire gauge decides which spool a robot will read. Where a maker publishes none of it, the page reports the answer as unpublished rather than deducing it from a photograph or a model name.