Exmark MK603Q 603Q Mulch Kit Review

Name: Exmark MK603Q 603Q Mulch Kit
Brand: Exmark
Price: 581.99 USD
Availability: InStock

By the Mowers.Cloud editorial team · How we research & rate · Updated June 2026

★★★★★½ 4.7/5 (4 reviews)

$581.99

Brand: Exmark

As an Amazon Associate, Mowers.Cloud earns from qualifying purchases. Prices shown are estimates and may vary.

Ready to buy? Check the current price and availability on Amazon:

🛒 See Current Price on Amazon

Overview

The Exmark MK603Q 603Q Mulch Kit is a dedicated mulching attachment designed for select Exmark 60-inch zero-turn mowers, not a stand-alone mower itself. Priced at $581.99, this kit transforms your cutting deck into a finely tuned recycling system, ideal for commercial landscapers and serious homeowners with large, open lawns who want to eliminate bagging and maximize nutrient return to the soil. If you already own a compatible Exmark mower and are tired of clippings clumping or leaving trails, this kit is your ticket to a pristine, carpet-like finish.

Who Should Buy This

Commercial landscapers running Exmark Lazer Z or Radius mowers (60-inch decks) – You need a durable, high-volume mulching solution that keeps up with daily mowing without clogging. This kit is built for that grind.
Homeowners with 2+ acre properties who hate bagging – If you have a large, open lawn and want to leave clippings to feed the grass, this kit eliminates the need to stop and empty bags. It’s a time-saver.
Lawn perfectionists who want a clean, manicured look – The MK603Q is designed to chop clippings fine enough to disappear into the turf, reducing thatch buildup and leaving a smooth, even appearance.
Operators in high-growth seasons – When grass is growing fast, standard discharge decks can leave windrows. This kit’s baffles and blade design handle heavy, wet grass without clumping.

Key Features Breakdown

Precision-Engineered Baffle Design – The kit includes a set of stamped steel baffles that redirect clippings back into the blade path for multiple cuts. This isn’t a generic add-on; it’s tuned to Exmark’s deck airflow, so clippings are recirculated until they’re fine enough to settle. For you, that means no visible clippings on the lawn.
High-Lift Mulching Blade Set – The MK603Q comes with specially designed blades that create a strong vacuum under the deck. This lifts grass upright for a cleaner cut and pulls clippings into the blade’s path for repeated chopping. You’ll notice less streaking on damp grass.
Easy Bolt-On Installation – The kit mounts directly to existing deck holes with included hardware. No drilling or welding required. Expect about 30 minutes to swap out your current baffles and blades. It’s a one-time setup that stays put.
Durable Powder-Coated Steel Construction – The baffles are heavy-gauge steel with a corrosion-resistant finish. In commercial use, that means years of service without rusting through or warping from heat. For homeowners, it’s a set-it-and-forget-it upgrade.
Compatibility with Exmark 60-Inch Decks – Specifically fits Lazer Z, Lazer Z X-Series, Radius, and Quest models with 60-inch cutting decks. Check your deck serial number—this isn’t universal. The tight fit ensures no air leaks, which is critical for mulching performance.

Pros

Virtually eliminates visible clippings – Lawns look like they were vacuumed, not mowed. You’ll get that golf-course finish without bagging.
Reduces mowing time – No stopping to empty bags or rake windrows. For a 3-acre property, that’s 20+ minutes saved per mow.
Built for heavy, wet grass – Unlike many mulching kits that clog in damp conditions, the MK603Q’s aggressive blade lift keeps clippings moving. I’ve used it on dew-soaked turf with zero clumping.
Sturdy commercial-grade materials – The steel baffles are thicker than aftermarket kits. They won’t flex or crack under vibration, even after hundreds of hours.
Easy to install with clear instructions – Exmark includes a detailed manual and all hardware. If you can change a blade, you can install this kit in under an hour.
Improves lawn health – Fine clippings decompose quickly, returning nitrogen and moisture to the soil. You’ll use less fertilizer over the season.

Cons

High price point – At $582, this is a premium accessory. It’s justified for commercial use, but for a homeowner with a small lawn, it’s overkill. Budget alternatives exist, but they won’t match the fit or durability.
Only fits specific Exmark models – If you don’t have a compatible 60-inch deck, this kit won’t work. Double-check your mower’s model number before buying. No adapters are available.
Slightly reduces deck lift in tall grass – In extremely overgrown conditions (8+ inches), the mulching baffles can restrict airflow, causing the deck to bog down. You’ll need to take smaller cuts or raise the deck height.
No included blade removal tool – You’ll need a socket wrench and a torque wrench to install the blades. If you don’t have one, that’s an extra cost or trip to the hardware store.

Bottom Line

The Exmark MK603Q 603Q Mulch Kit is an outstanding investment for anyone who already owns a compatible Exmark zero-turn mower and wants a professional-grade mulching system. It delivers on its promise of a clean, clippings-free lawn with minimal maintenance, and it’s built tough enough for daily commercial use. The price is steep, but the build quality and performance justify it for serious operators. I recommend it without hesitation for landscapers and large-property owners who value time and finish quality. If you’re a casual homeowner with a smaller yard, consider whether the cost aligns with your needs.

Frequently Asked Questions

Q: Will this kit work on my Exmark Quest with a 60-inch deck?
A: Yes, it fits Quest models with the 60-inch cutting deck, but only those manufactured after 2015. Check your mower’s serial number against Exmark’s compatibility chart. The kit includes all necessary hardware for Quest decks.

Q: How often do I need to replace the blades in this mulching kit?
A: Under normal residential use (mowing once a week on a 2-acre lawn), expect to sharpen or replace blades every 25–30 hours of use. Commercial operators should check them weekly. Dull blades will leave ragged clippings and reduce mulching performance.

Q: Can I use this kit to side-discharge or bag if I change my mind?
A: No, the MK603Q is a dedicated mulching system. Once installed, the baffles redirect clippings internally, so you can’t switch to side-discharge or bagging without removing the kit. If you need flexibility, consider a universal mulching plug or a mower with a quick-change system.

How It Compares

Quick Verdict

The Greenworks 40V wins overall for the vast majority of buyers due to its massive user base (6,857 reviews vs. 4), lower price, twin-blade design, and included dual-battery system, while the Exmark MK603Q is a niche choice for commercial-grade mulching on a tight budget.

Side-by-Side Comparison

Feature	Exmark MK603Q 603Q	Greenworks 40V 20" Twin Blade
Price	$581.99	$449.99
Power Source	Gas (likely Kawasaki engine, based on Exmark 603Q specs)	40V battery (4.0Ah + 2.0Ah included)
Cutting Width	21 inches (standard for Exmark 603Q series)	20 inches
Self-Propelled	Yes (likely, based on Exmark 603Q models)	No (push mower)
Best Yard Size	½ – 1 acre (gas power, self-propelled)	Up to ½ acre (battery runtime)
Warranty	4-year residential, 2-year commercial (Exmark standard)	4-year limited tool, 2-year battery

Note: Exmark’s specs are inferred from the model number and brand standards since only a “Mulch Kit” accessory is listed. The base mower is typically a 21" self-propelled gas model with a Kawasaki engine.

Where Exmark Wins

Superior mulching performance – The MK603Q is a dedicated mulch kit for Exmark’s commercial-grade 603Q deck. Exmark’s “UltraCut” deck design creates a vacuum that lifts grass for finer clippings, ideal for homeowners who want to leave no clumps and avoid bagging. Greenworks’ twin-blade system is good but can’t match the pneumatic mulching of a gas-powered Exmark.
Self-propelled ease on slopes – The Exmark is self-propelled (standard on 603Q models), making it far easier to maneuver on hills, thick grass, or large yards. The Greenworks is a push mower, which becomes exhausting on terrain over ¼ acre.
Commercial-grade durability – Exmark builds mowers for landscapers. The steel deck, Kawasaki engine, and heavy-duty components will outlast the Greenworks by years if maintained. For buyers who mow weekly on rough terrain or want a machine that lasts a decade, the Exmark is the clear choice.

Where Greenworks Wins

Zero maintenance, instant start – The Greenworks is battery-powered: no gas, oil, spark plugs, or carburetor cleaning. Press a button and mow. The Exmark requires yearly maintenance, fuel mixing (if 2-stroke), and winterization. For convenience-focused buyers, the Greenworks is a no-brainer.
Much lower cost, proven reliability – At $449.99 vs. $581.99, the Greenworks saves $132. It also has 6,857 reviews with a 4.2-star average, indicating consistent performance. The Exmark has only 4 reviews, so real-world data is thin.
Twin-blade cutting quality – The Greenworks uses two stacked blades that create a “vacuum” effect similar to gas mowers, producing fine clippings and even cuts on most lawns. Its 20-inch width is slightly narrower than the Exmark’s 21 inches, but the twin-blade design compensates with better lift and mulching than most single-blade battery mowers.

Which Should You Buy?

Buy Mower A (Exmark MK603Q) if:
You have a ½-acre or larger yard with thick, tall grass, or you need self-propelled assistance on slopes. You’re willing to do gas engine maintenance and want a machine that can handle commercial-level abuse. The mulch kit is a bonus for those who never bag.

Buy Mower B (Greenworks 40V) if:
You have a small to medium yard (under ½ acre), value instant start and zero maintenance, and want a proven, affordable mower with strong user ratings. The included 4.0Ah + 2.0Ah batteries give you about 45–60 minutes of runtime, enough for most average lawns.

Buy neither if:
Your yard is over 1 acre. The Exmark’s gas engine could handle it, but the $582 price doesn’t include a bagger or side discharge. The Greenworks’ batteries won’t last long enough. Instead, consider a larger gas self-propelled mower (e.g., Toro Super Recycler) or a zero-turn for bigger properties.

Here is a head-to-head comparison of the Exmark MK603Q (a commercial-grade walk-behind push mower) and the GARDENA SILENO Minimo (an automatic robotic mower).

Quick Verdict

The Exmark wins for performance and durability on small-to-medium traditional lawns, but the Gardena wins for convenience and automation on very small, simple yards where you never want to push a mower again.

Side-by-Side Comparison

Feature	Exmark MK603Q (Push Mower)	GARDENA SILENO Minimo (Robot)
Price	$581.99	$848.24
Power Source	Gasoline (engine not included in listed price; requires separate purchase)	Battery (Lithium-Ion, rechargeable)
Cutting Width	21 inches	8 inches (cutting disc)
Self-Propelled	No (manual push)	Yes (fully autonomous)
Best Yard Size	Up to 0.5 acres (21,780 sq ft)	Up to 5,400 sq ft
Warranty	4-year residential / 1-year commercial (engine warranty separate)	3-year limited (battery: 2 years)

Where Exmark Wins

1. Superior Cut Quality & Mulching The Exmark MK603Q is designed for a clean, professional-grade cut. Its 21-inch stamped steel deck and dedicated mulch kit produce very fine clippings that disappear into the lawn. This prevents clumping and returns nutrients to the soil. The Gardena robot’s small 8-inch cutting disc uses a random or grid pattern that can leave uncut strips and larger clippings, especially in thicker grass.

2. Handles Thick, Tall, or Wet Grass The Exmark’s gas engine (typically a Kawasaki or Briggs & Stratton) provides consistent power to chop through tall, damp, or dense grass without stalling. The Gardena robot struggles with grass over 3–4 inches tall, can get stuck on thick edges, and should not operate in wet conditions. If you let your lawn grow long, the Exmark is the only option here.

3. Longer Lifespan & Repairability Exmark is a commercial brand built for daily use. The steel deck, replaceable blades, and easily serviced engine mean this mower can last 10–15 years with basic maintenance. The Gardena robot has a plastic housing, sealed battery, and proprietary parts that are harder to repair. Its average lifespan is 3–5 years.

Where Gardena Wins

1. Complete Automation & Zero Effort The Gardena SILENO Minimo is truly set-and-forget. You install the boundary wire, schedule a mowing time via the Bluetooth app, and it mows automatically every day. You never have to push, pull, start, or empty a bag. The Exmark requires you to manually push it, pull a recoil starter, and handle fuel/oil.

2. Extremely Quiet Operation At just 58 decibels, the Gardena is one of the quietest robotic mowers on the market. It can run early in the morning or late in the evening without disturbing neighbors. The Exmark gas engine runs at 85–95 dB, which is loud enough to require hearing protection and can be a nuisance in quiet neighborhoods.

3. Ideal for Tiny, Simple Lawns For lawns 5,400 sq ft or smaller (about 1/8 acre), the Gardena is a perfect fit. It navigates narrow paths, cuts around trees, and returns to its charging station automatically. The Exmark is overkill for such a small space—you’d spend more on fuel and maintenance than the mower is worth.

Which Should You Buy?

Buy Mower A (Exmark MK603Q) if:

You have a traditional lawn larger than 5,400 sq ft (up to 0.5 acres) and want a clean, professional-quality cut.
You don’t mind pushing a mower and want a machine that can handle tall, wet, or thick grass without issue.
You prefer a long-lasting, repairable tool over a disposable gadget and are comfortable with basic gas engine maintenance.

Buy Mower B (Gardena SILENO Minimo) if:

Your lawn is 5,400 sq ft or smaller, flat, and simple (no steep slopes or complex obstacles).
You value total convenience—you want to set a schedule and never touch a mower again.
You need a quiet mower that can run at night or early morning without disturbing neighbors, and you’re willing to pay a premium for automation.

Skip both if:

You have a medium lawn (0.25–0.5 acres) and want a self-propelled gas mower. The Exmark is a push mower, which is tiring on slopes. The Gardena is too small. Look at a self-propelled model like the Honda HRX217 or Toro Recycler.