Mulching vs High Lift vs Standard Blades – Which Is Best?

When it comes to lawn mowing, the type of blade you use is one of the most important factors in achieving a healthy and well-manicured lawn. Different blades offer unique benefits for various types of grass and terrain. Understanding the differences between mulching, high lift, and regular blades can help you choose the best blade for your lawn mowing needs. 

Lawnmower Blade Profile and Function

I think that we all appreciate the ultimate goal of any lawn mower blade design is to cut grass as efficiently and evenly as possible. Well, this is true of standard lawnmower blades for sure, but standard blades are a one-size fits all approach. Depending on what performance we require, different mower blade profiles can serve us better in different situations, for example when mulching or requiring side discharge.

Standard blades also often referred to as low-lift blades, feature a relatively flat profile, with a moderately curved outer edge. This profile creates lower levels of suction, and a greater degree of range when lowering the deck to make shorter cuts. They are also well suited to mowing on sandy or gravelly surfaces, making the standard blade a versatile option.

High-lift blades are similar in profile to low-lift blades. The primary difference is the angle of the curve on the blade’s outer edge and the slight teardrop shape. The steeper blade angle creates more suction or uplift and delivers a larger upright surface area to expel the grass clipping from the deck. Making the high-lift blade a great option for side discharge, or wet or long lawns.

Mulching blades also known as 3-in-1 blades, can be used to bag, discharge, or mulch clippings. Their curved blade and larger cutting edge, serve to lift and recirculate the clippings within the cutting deck, allowing for multiple blade passes to re-cut the grass into smaller pieces. Lacking the steeply curved edges and suction of the high-lift blade, the mulching blade deposits fine clipping on the lawn surface.

Standard Mower Blade Design and Function 

A standard mower blade (low-lift) is the most commonly used mower blade due to its versatility. They are designed to provide a well-groomed lawn with an even cut. The profile cuts grass evenly and efficiently and is best used on lawns with relatively shorter lengths lawns.

The flat cutting blade faces downwards to cut the grass, while the curved outer edge faces upwards, preventing grass clippings from becoming tangled in the blade. The length of the regular mower blade typically ranges from 19-22 inches, and the width from 2.5-3.5 inches. The design helps promote a clean-cut and uniform grass height across the lawn.

Mechanical Action: Whilst spinning, the cutting edge of the blade slices through the grass with a scissor-like motion. A combination of centrifugal force and air pressure creates this motion. As the blade spins, the centrifugal force pushes the air outward and creates a vacuum in the blade’s center. 

This vacuum pulls the grass towards the blade, allowing it to be cut. Additionally, the blade is designed with a sharp edge angled slightly downward to allow for a cleaner cut. 

Air Circulation: Standard blades are designed to create a moderate vacuum effect, pulling the grass clippings into the chamber and creating a vortex of air around the blades. This helps to reduce clogging within the mower deck while also creating a more efficient cutting action. The air-circulating blade also helps to keep the grass blades upright and increases the quality of the cut and reduces scalping.

The vacuum effect also helps to suck in debris and clippings, resulting in a clean, finished cut.

Grass Clumping: Grass clumping is a common problem for many mowers, but it can be reduced or eliminated by the type of blade used. Regular blades create a moderate amount of lift and air circulation, which helps prevent clumping. For long grass or wet grass, the high lift blade is preferred due to the increased suction and airflow created.

Suction Power: Standard mower blades generate a moderate amount of suction, which has its benefits and limitations. Low suction is useful when mowing over dusty or sandy surfaces, keeping airborne particles to a minimum. Whereas the standard blade often struggles in long or wet grass compared to the high-lift blade. 

Pros and Cons of Regular Mower Blades

Pros:

• Versatile and can be used in many different mowing situations.
• Have a long lifespan due to their sturdy design and construction.
• Great for cutting and bagging grass clippings.
• Can handle thicker grass and weeds.
• Easy to sharpen and maintain.
• Low cost compared to other blade types. 
• Helps provide an even cut throughout your lawn.

Cons: 

• Moderate air circulation, meaning lower control with the clipping distribution.
• Increased clumping with wet or long grass, resulting in more clean-up.
• Lower suction so not ideal for side discharge and cannot mulch

High Lift Blade Design and Function  

High-Lift Blades are designed to produce a strong lift force, enabling the blade to move more air and cut grass faster than traditional mower blades. They are usually longer, wider, and curved, increasing suction power as they cut through the grass. The design also helps to reduce clumping and improve the dispersal of clippings over the lawn.

High Lift Blades are designed to create better air circulation, which can help dry out the lawn quicker and help prevent lawn diseases such as fungus or brown patches. The increased suction power generated by these blades also helps create a cleaner cut and can reduce tear-out or ragged edges on your lawn.

The increased lift force generated by high lift blades helps them stay off the ground and creates a better cutting angle, providing a smoother cut. This also reduces the energy required for each mowing session, resulting in a less tiring job for the user.

Mechanical Action: The high lift blade is designed to create an air cushion between the blade and the grass when in motion. This air cushion reduces friction and resistance while the blade cuts, resulting in a smoother and more consistent finished product.

The larger, thicker edges of the high lift blades also lift up the grass before cutting it for improved performance. As the mower moves forward, clippings are propelled forward into the grass bag or into a side discharge chute for easy disposal.

Air Circulation: When the mower is in motion, the larger edges of the blade lift up the grass and essentially scoop out a pocket of air between them. This pocket of air then creates a cushion that reduces friction and resistance from the blade cutting through the grass. As the blade passes through, it sucks up clippings and propels them forward into either a side discharge chute or a grass bag for easy disposal.

Grass Clumping: A high-lift lawnmower blade is an efficient way to reduce grass clumping. The larger edges of the blades act like a scoop, lifting up the grass before cutting it which significantly reduces clumping. The clippings are propelled forward into either a side discharge chute or a grass bag for easy disposal after they have been cut.

Suction Power: High-lift lawnmower blades create powerful suction capable of pulling grass clippings up into the deck and expelling them for side discharge or bagging. The fan-like suction makes high lift blades ideal for cutting tall, compact grass.

Pros and Cons of High-Lift Blades

Pros:

• Improved performance due to an air cushion between the blade and the grass.
• Reduced friction and resistance while cutting.
• Clearer finished product with a more consistent cut.
• More efficient at picking up clippings for easy disposal.

Cons: 

• Prone to damage from pebbles and stones that get picked up in the cutting path.
• Higher risk of breakage during regular operation.
• More expensive than other types of mower blades.

Mulching Blade Design and Function

Mulching blades are designed to cut grass clippings into smaller pieces. This allows for the clippings to be reincorporated into the soil and replenish nutrients that have been used up. Mulching blades usually feature a curved design which creates suction when cutting grass, allowing for the better reincorporation of the clippings.

Mulching lawnmower blades can also provide better air circulation as they create turbulence when spinning. This allows the grass to stand upright and promotes healthier growth. Mulching blades tend to spin faster than regular blades and are less likely to cause damage to grass due to their curved shape.

When it comes to grass clumping, mulching blades are highly effective. The curved design helps reduce the clippings’ size, resulting in a more even dispersal. This eliminates the need for frequent rake-ups and reduces the time needed to maintain a healthy lawn.

Mechanical Action: Mulching blades have a curved design that works by cutting the grass multiple times, creating small pieces as it rotates. This helps to break down the clippings faster and makes them easier to decompose back into the soil. The curved shape also creates a powerful suction that helps move the clippings through the deck for efficient cutting.

Air Circulation: The curved blade helps to create relatively powerful suction and excellent air circulation. It’s the exceptional air circulation that retains the grass clipping in an air vortex, allowing the blade to make multiple cuts, reducing the clippings into small fragments of grass.

Grass Clumping: The mulching blade is designed to be highly efficient at reducing grass clumping. The curved shape and powerful suction of the mower blade pull the grass clippings up into the deck and evenly spread them around the blade. This helps to keep the grass from clumping together, allowing for smoother cutting.

Suction Power: The curved design that lends itself so well to air circulation, also generates excellent levels of suction. The mulching blades sit above the standard blade and high-lift blade in terms of suction power.

Pros and Cons of Mulching Blades

Pros:

• Increases decomposition speed by accelerating microbial activity
• Reduces grass clumping and results in smoother cutting.
• Creates a powerful suction that ensures the grass is evenly distributed.
• Can mow large areas in less time due to increased efficiency.

Cons: 

• Can be more expensive than other types of blades due to the additional features it offers.
• May require extra maintenance, as mulching blades can quickly become clogged with debris.
• May not be suitable for wet or dense grass conditions, as the extra suction may cause the mower to bog down.

Mulching Vs High Lift Vs Standard Blades Comparison

Here is a comparison between high lift, mulching, and regular blades that describes their physical attributes, and characteristics. 

Blade Type	Profile	Function	Characteristics
Standard Blade	Low profile	Versatility	Low profile cut
High Lift Blade	Curved edges	Long or damp grass	Strong suction
Mulching Blade	Curved blade	Mulching grass clippings	High suction and air circulation

Which is Better High Lift or Mulching Blades? 

It depends…

If I could only select one type of lawnmower blade then I would recommend high lift. They offer good versatility, create excellent airflow and suction to aid side discharge, and have the capability to mow longer lawns.

Mulching blades on the other hand bring other qualities. If you regularly mow the same lawn, then you know the grass is never going to be too long for a mulching blade. This means with regular mowing you can mulch consistently delivering precious nitrogen-packed clippings back onto your grass.

Ultimately, there is no one-size-fits-all answer when choosing between high-lift or mulching blades. Consider both pros and cons before deciding what works best for you and your lawn.

Frequently Asked Questions

Reference

Troy-Bilt – Mulching Vs High Lift Blades