Dealing with Lawn Clippings: Mulching, Bagging, Side Discharge and Rear Discharge

download (7)Which type of deck is right for your needs? Whether you’re buying a walk-behind for a small lawn or you’re a commercial operator that needs to deliver beautiful lawns quickly, there are a lot of considerations to be made when choosing how your mower deals with clippings.

Side Discharge

Almost every mower on the market can send clippings out of a chute, although there are some serious disadvantages with this method. The clippings are concentrated into a thin stream, leaving long piles behind. Add in some wind, and the operator will get a nice coating of clippings and dirt on them while mowing. Hit an object? The velocity from the edge of the blade can propel it at speeds that can do some serious damage. Have a deck with multiple blades? More power is needed to push clippings along the deck to the chute.

Why is side discharge still an option when it has so many problems? It’s simple, fast and works in any condition. Side discharge equipment is less complex, and this type of mowing can handle wet and tall grass with ease. When you have to mow in less than optimal conditions, this is a great option.


Mulching cuts down the clippings into small pieces before they fall to the ground, helping them integrate into the thatch that covers the turf’s surface. These tiny pieces are digested quickly by microorganisms, returning their nutrients to the soil.

Old mowers used pairs of blades situated 90 degrees from each other in an attempt to cut the clippings multiple times before they hit the ground. Modern decks pair high lift blades with tall mowing chambers, using force and air flow to bounce clippings around for multiple cuts. Once a piece is small enough, it can fall through the blades and onto the turf. However, all that extra cutting can cause problems on tall and wet grass, clogging the deck and leaving behind large clumps of grass.

Constructed vs. Stamped Decks

The shape of the deck can have a major effect on mulching quality. The smooth curves on the inside of stamped decks help maintain vacuum for a fine cut, while constructed decks have box-like interiors that created dead spaces the grass can fall through. Some manufacturers have turned to hybrid designs that add curved plating to the inside of constructed decks, providing better suction while retaining the durability of a thick steel exterior.


Bagging can be used to remove seeds from weeds when they’re germinating and reduce the amount of thatch for better penetration of water, seed, and fertilizer.

Large commercial mowers use bagging systems that integrate an impeller. This works like an onboard lawn vac, actively pulling clippings from the deck and compacting them to increase the amount of material that can be held inside the bags.

Rear Discharge

When you need to quickly mow areas in residential areas with lots of landscaping, nothing beats a rear discharge deck. They don’t have a chute, so they’re as narrow as possible. The clippings are spread across the entire width of the deck, which reduces clumping. This spread also lets the blades eject clippings directly, reducing noise and power requirements.

These abilities come at the cost of flexibility. A traditional deck design can be set up for side discharge, mulching or bagging, but the wide outlet of a rear discharge deck means it can only discharge clippings. There are specialty mowers that combine a rear discharge deck with a specially constructed bagging system to get the close clipping advantages of these decks, but these models tend to be slow and very pricey.

Get the Deck You Need

Whether you’re looking to buy a new mower or make some changes to your current deck, you can get the advice and support you need at Shank’s Lawn Equipment. We’ve been helping homeowners and professionals alike for over 30 years, selling and servicing a wide range of popular brands. Visit us at our shop located at 4900 Molly Pitcher Highway in Chambersburg, PA. That’s just off Rt. 11, or you can drive in from I-81 by taking Exit 10 to Marion.

Not in the area? We can ship parts and accessories for mowers from a wide range of manufacturers, letting you set up your current deck for mulching, bagging and side discharge or just get the parts you need to repair it. Visit us online at

This entry was posted in Uncategorized and tagged , , . Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *