Every haymaking operation begins with a mower, and the mower you pick sets the ceiling on what the rest of your equipment can achieve. A poor cut leaves stubble too tall, ash content too high, and windrows uneven before they even reach the rake. A good cut makes everything downstream easier.
Three families of hay mower dominate the market: disc mowers, drum mowers, and sickle bar (cutter bar) mowers. Each has a clear niche, and the right choice depends on your hectares, your tractor, your crop, and how much time you can give to maintenance.
This guide compares all three head-to-head — on cutting speed, durability, cost, and the things that actually matter once the machine is in your field.
The 30-second decision matrix
If you only have a moment, this is the short answer most operations land on:
| Your situation | Best fit |
|---|---|
| Large fields (>50 ha), high throughput, modern tractor (60+ HP) | Disc mower |
| Small to mid-size operation (<30 ha), tight budget, older or smaller tractor (35–60 HP) | Drum mower |
| Hilly, rocky, or contour-heavy ground; very small acreage; trimming work | Sickle bar mower |
| Hay sold by quality / leaf retention | Disc mower (or disc mower-conditioner) |
| Hay cut wet, in dewy mornings, or in tough lodged crop | Drum mower |
Now to the detail behind those calls.
How each mower actually works
The cutting mechanism is the easiest place to start, because it explains every downstream difference in performance, cost, and maintenance.
Sickle bar mower
The oldest of the three. A long horizontal bar carries fingered guards, and a reciprocating knife (a series of triangular blades) slides back and forth between the guards, cutting hay in a scissor-like action.
Sickle bars cut at relatively low speeds — typical ground speed is 5–8 km/h. They are mechanically simple, cheap to repair, and gentle on grass. They are also fussy: they clog in damp or dense crop, plug on already-cut grass, and need careful adjustment to keep their cutting edges aligned.
Most modern hay operations have moved on from sickle bars for primary mowing, but they remain valuable for trimming around fence lines, water bodies, and on small orchards where finesse matters more than speed.
Drum mower
A drum mower uses two (sometimes three) large counter-rotating drums driven from a gearbox above the cutter assembly. Each drum carries 3–4 free-swinging blades around its base. The drums rotate inward toward each other, drawing the cut crop into a windrow between them.
The whole drum assembly slides along the ground on a “dish” bearing, which controls cutting height and lets the mower shed obstacles. Because the drive gears are above the cutting plane, drum mowers tolerate impact damage well and rarely sustain expensive gearbox failures.
Drum mowers windrow naturally — the crop falls in a relatively narrow strip between the drums. This is convenient for raking but can slow drying without tedding.
Disc mower
A disc mower mounts multiple smaller discs (typically 6 to 10, depending on cutting width) along a horizontal cutter bar. Each disc carries 2 free-swinging blades. The discs are driven from below by gears or a shaft running inside the cutter bar.
Disc mowers cut at high ground speeds — 12–18 km/h is achievable in good conditions. They handle thick and lodged crop well, leave a uniform spread or a configurable windrow, and dominate the professional and large-farm market worldwide.
Their weakness is impact damage: striking a rock or fence post hard can break a disc, damage the cutter bar, or destroy the gear case — and disc mower repairs are not cheap.
Cutting speed and throughput
The single most visible difference between these mowers is how fast you can finish a paddock.
| Mower type | Typical ground speed | Hectares per hour (single pass) |
|---|---|---|
| Sickle bar (1.8 m) | 5–8 km/h | 0.9–1.4 ha/h |
| Drum mower (1.8 m) | 10–15 km/h | 1.8–2.7 ha/h |
| Disc mower (2.4 m) | 12–18 km/h | 2.9–4.3 ha/h |
| Disc mower (3.2 m+) | 12–18 km/h | 3.8–5.8 ha/h |
These are best-case numbers in clean, level fields. Headlands, turns, and uneven crop cut real-world throughput by 25–35%.
For perspective: cutting 100 ha with a 1.8 m sickle bar mower takes around 75–85 working hours. The same job with a 3.2 m disc mower takes 18–24 hours. For commercial operations, that productivity gap easily justifies the higher purchase price of a disc machine.
Cost: purchase price and operating cost
Real-world prices vary by region and brand, but the relative positioning across the three categories is consistent worldwide.
Purchase price (indicative ranges, USD)
- Sickle bar mower (1.8–2.1 m): $1,500–$4,000 new
- Drum mower (1.6–2.4 m): $3,000–$8,000 new
- Disc mower (2.0–2.4 m): $6,000–$15,000 new
- Disc mower-conditioner (2.4–3.2 m): $15,000–$35,000+
- Disc mower (3.2 m+): $12,000–$25,000
A second-hand market exists for all three, with sickle bars and older drum mowers especially affordable.
Operating cost
The picture changes once you factor in repair likelihood.
- Sickle bar: Cheap parts, frequent minor adjustments, knife sections need regular replacement. Low total cost on small acreage.
- Drum mower: Free-swinging blades are inexpensive and quickly replaced. Belts (on belt-driven models) need occasional replacement. Gearboxes are very durable. Low to moderate total cost.
- Disc mower: Free-swinging blades are inexpensive. However, hitting a solid object can damage discs, the cutter bar, or the gear train, with repair bills running into thousands. Modular cutter bars (where individual disc modules can be replaced separately) have made this less catastrophic, but the risk remains. Moderate to high total cost.
For high-acreage operations the throughput gain of a disc mower more than offsets its operating cost. For low acreage, the simpler economics of a drum mower usually win.
Tractor horsepower requirements
Mowers are PTO-driven and the right tractor matches both the cutting width and the mower’s mass.
| Mower type / size | Minimum PTO HP | Comfortable PTO HP |
|---|---|---|
| Sickle bar (1.8–2.1 m) | 25–30 HP | 35–45 HP |
| Drum mower (1.6 m, 2-drum) | 30–35 HP | 45–55 HP |
| Drum mower (2.4 m, 3-drum) | 50–60 HP | 65–75 HP |
| Disc mower (2.0 m) | 40–50 HP | 55–65 HP |
| Disc mower (2.4 m) | 55–65 HP | 70–85 HP |
| Disc mower (3.2 m) | 80–95 HP | 100–120 HP |
| Triple-mower combinations | 200+ HP | 250–350 HP |
Drum mowers are deceptively heavy — a 2.4 m drum mower can weigh 600–800 kg. Smaller tractors may have the PTO horsepower but not the front-end ballast or the lift capacity to safely manage the machine in transport.
Field performance: where each one wins
Where the disc mower wins
- Large, clean fields with good visibility and few obstacles
- Heavy, lodged or wet crop where sickle bars would plug
- Premium hay markets where uniform stubble height and high leaf retention drive prices
- Operations sized to a 2.4 m+ working width with the tractor to suit
If your tractor is over 60 PTO HP and your fields are over 30 hectares of relatively clean ground, the disc mower is almost always the right answer.
Where the drum mower wins
- Mid-size operations (10–40 ha)
- Older or smaller tractors (35–55 HP) where a disc mower would overload the rear axle
- Rocky or unfamiliar fields where impact damage risk on a disc machine is high
- Tight budgets or hobby operations cutting 1–2 times per year
- Wet or dewy conditions where the heavy drum mass keeps cutting through tough material
Drum mowers also have a quiet but real advantage: they almost never break in a way that strands you. Their failure modes are gradual (worn belts, dull blades), not catastrophic.
Where the sickle bar wins
- Trimming work along fences, roads, water bodies
- Very small acreage (under 5 ha) with old, low-HP tractors
- Steep, contoured ground where a heavier mower would slide or destabilise
- Niche organic / heritage operations that value gentle cutting action
Sickle bars are not the right tool for primary haymaking on most modern farms, but they remain a useful second mower for finishing work.
Cutting quality: leaf retention and stubble height
For premium hay markets — export oaten hay, dairy lucerne, fine grass hay — cutting quality is the most important spec, not throughput.
Leaf retention. Disc mowers, with their gentle, free-swinging blade action and cleaner cut, retain leaf better than drum mowers in dry conditions. Sickle bars are also very gentle but slow.
Stubble height. All three mowers can be set to different stubble heights, but disc mowers offer the finest adjustment. For lucerne, 5–7 cm stubble protects the crown from damage and supports faster regrowth. Drum mowers tend to cut a touch lower than ideal unless carefully adjusted.
Crop conditioning. Disc mowers can be paired with conditioning rolls or impellers (the “discbine” or “mower-conditioner” configuration), which crimp or scuff the stems to dramatically reduce drying time. Drum mowers can be fitted with whip conditioners on some models, but the conditioning is less effective than rolls. Sickle bars are typically used with separate conditioner units. For dairy operations producing haylage, a mower-conditioner is the gold standard.
Maintenance: time on the wrench
A real-world maintenance ranking, from least demanding to most:
- Drum mower — Belt tensioning twice a season, blade replacement as needed, occasional gear oil top-up. Few moving parts.
- Sickle bar — Frequent minor adjustments, knife and guard replacements, but parts are cheap and the work is quick.
- Disc mower — Less frequent attention, but when something goes wrong, the work is more involved and parts are more expensive. Cutter bar oil checks, disc module inspection, blade replacement, knife bolt re-torque.
For operators less mechanically inclined, a drum mower has the advantage of being almost forgiving. Disc mowers reward operators who keep up with their inspection schedule and punish those who don’t.
A clear recommendation framework
Here is how we would line it up for an international buyer building a new haymaking lineup:
If you have a small farm (under 15 ha), a 35–55 HP tractor, and you mostly want hay for your own livestock:
Buy a 1.6–2.0 m drum mower. It will cut your acreage in a day, last for many years, and you will rarely have to call anyone.
If you have a mid-size farm (15–50 ha), a 55–85 HP tractor, and you sell some hay:
A 2.4 m disc mower or a 2.4 m drum mower both work. The disc machine pays back faster on larger acreage; the drum machine forgives more in tough conditions.
If you have a large operation (50+ ha) or are a contractor:
A 3.0 m+ disc mower-conditioner is the standard. Look at modular cutter bar designs for serviceability.
If you are running a hobby farm under 5 ha or just need trim mowing:
A used 1.8–2.1 m sickle bar mower is a perfectly good answer.
Frequently asked questions
Q: Is a drum mower or disc mower better for small farms?
A: For most small farms (under 30 ha) a drum mower is the better economic choice — lower purchase price, simpler maintenance, and forgiving of impact damage.
Q: Can I use a disc mower for trimming around obstacles?
A: Disc mowers are not ideal for tight trimming. Their wide cutting width and the cost of impact damage make a sickle bar (or a small flail mower) a better tool for that job.
Q: Do I need a mower-conditioner?
A: For dairy operations producing haylage, yes — the conditioning step can shave a half-day off drying time. For dry hay sold to horse or beef markets, plain mowers with separate tedding may be adequate.
Q: How often do disc mower blades need replacing?
A: Free-swinging blades typically last 200–600 hectares depending on conditions. Blades are inexpensive but the carrier bolts must be torque-checked at every change.
Q: Why are drum mowers so popular in some countries and not others?
A: Drum mowers were a European design and remain dominant in much of Eastern Europe, parts of Asia, and small-farm regions worldwide. North American and Australian large-farm operations have largely standardised on disc mowers because of throughput.
Next step
Picking the right mower is the foundation of every kilogram of hay you bale that season. If you want to compare specific models for your tractor and acreage, browse our Серія косарок — each product page lists working width, PTO HP requirements, weight, and recommended tractor categories.
Once you’ve picked your mower, the next decision is how to gather the cut crop into windrows. See our companion guide: Wheel Rake vs. Rotary Rake vs. Twin Bar Rake: Which Windrow Suits Your Baler?
About the author: This guide was written by the technical team at Australia baler-hay Co., Ltd, an international supplier of haymaking equipment with 24/7 technical support for export buyers worldwide.