PRODUCT TRENDS - Mulch Ado About Nothing

Mowers cut grass. But mulching mowers really cut grass. That’s the primary distinction in a nutshell. But there’s much more worth knowing about this particular client-pleasing powerhouse.

As parts of the country begin to pass legislation to keep grass clippings out of landfills, and environmentally conscious contractors look for cost-effective ways to fertilize, mulching mowers are beginning to take a more prominent place in the landscape market. Apart from the aesthetic appeal of the finer turf clippings they discharge, mulching mowers have also proven themselves to be a time-efficient alternative to catching, hauling and disposing.

WHY MULCH? The first patent on a mulching mower design was filed in 1961, according to Ruthanne Stucky, marketing director, Grasshopper, Moundridge, Kan. "When this patent expired in 1978, a couple of other companies came out with mulching models, but it wasn’t until the early 1990s that mulching experienced a major resurgence," she says, pointing out that one reason for the resurgence was the dilemma of turf clipping disposal. "When landfills began increasing their tipping fees and eventually closing to landscape debris, contractors discovered the advantages of mulching. By returning clippings to the soil, they can reduce fertilizer inputs and improve the health of the turf while reducing disposal costs and the quantity of yard waste."

"Catching used to be the big thing," explains Ken Raney, advertising manager, Hustler Turf Equipment, Hesston, Kan. "People would say, ‘I’ll just pick it up. It looks better.’ But that was before the environmental issues really began surfacing," he says. "People became more aware of the fact that when you haul that stuff away, it’s just being piled into a landfill.

"Mulching leaves a better finished appearance than regular side discharge, while it’s returning most of the nutrients to the soil," Raney adds.

Another related benefit of mulching turf is that it reduces thatch buildup. As Stucky explains: "Microorganisms that thrive while decomposing mulch clippings also break down adjacent thatch," she says. "This combination of microbial activity and decomposition improves the texture and nutrient contents of the soil."

"Catching will always look better because it leaves nothing behind, but it’s also a lot more labor intensive and it also removes all the nutrients in the clipped grass blade," Raney points out, adding that he’s heard many contractors complain that when they catch, they also have to fertilize more often. "So there’s a lot of value right there. We all want our grass to look nice, and if you don’t want to catch, mulching is about the only other thing you can do."

HOW IT’S DONE. But what exactly does a mulching mower do that leaves a yard looking cosmetically better than it would if cut by a standard mower? Raney explains that a mulching unit chops the grass more times than a regular blade on a typical mower. "With a regular mower you could have 2-inch blades lying on the grass and the problem with long blades is that they don’t filter down between growing blades to the soil," he says. "They sit on top, dry out in the sun and look bad."

Stucky explains that discharging clippings to the side distributes longer clippings on the surface of the lawn. "However, a mower with a mulching deck cuts and recuts clippings and directs these smaller clippings downward, deep into the grass bed."

The difference between a mulching mower and a standard mower is that a mulching mower is equipped with a deck that provides that second thorough chop to the turf blades. Raney explains that most mulching decks are just a traditional deck with a pan (or restriction plate) underneath it. "It isolates each mower blade so that they are essentially like an independent mower," he says, adding that the pans deflect the grass back up into the blades to get chopped up a few more times.

Stucky explains that mulching decks are generally purchased in the form of kits that can easily be installed on a standard mower. "They usually include shrouding, blades and a restriction plate, which are designed to work together creating the air flow that suspends clippings for repeated cutting and then discharges them down into the grass bed," she clarifies.

"There are three pans under a typical mulching deck, so to install you’d have to take the blades off, bolt the pans in there and put the blades back on," Raney describes. "And most are mid-mount machines, which means they’d have to be hoisted up to do this. So there’s a lot that can go into installation and removal with the non-dedicated mulching kits but most decks can be installed fairly quickly. It might take up to two hours, but after a few times most contractors can get that installation time down to a half-hour or so."

Raney adds that some manufacturers now offer dedicated mulching decks. "There are also catching decks that can be switched out to side discharge decks," he says.

According to Stucky, an optional mulching package costs about $200 to $250, dependent on deck size. Raney estimates their cost at a comparable $150 to $350, dependent on the manufacturer. "That’s the cost of mulching components – about $100 – plus blades," he says.

However, even after a mulching deck is purchased and installed, there are still a few things to consider before hitting the turf.

TIPS FOR SUCCESS. While mulching is overall less labor intensive than bagging, taking a mulching deck out onto a customer’s property requires some forethought and knowledge of the most appropriate conditions for mulching. For example, Stucky explains that the best results for mulching occur with regular mowing so that not more than one-third of the length of the grass blade will be removed. "Also, sharp blades are essential, and mulching blades may require more frequent sharpening since clippings are cut finer and recut several times," she says.

"Mowing grass about ½-inch taller than normal will aid in hiding the clippings and, incidentally, help to conserve moisture and allow grass plants to develop a good canopy and stronger root system," Stucky instructs. She also points out that, depending on the material and the ground speed of the mower, clippings will be reduced to about 3/8 -inch in length before being discharged down into the grass bed. At this size, the clippings tend to disappear into the turf. "Many people say they can’t tell whether the clippings have been mulched or collected," Stucky shares. "When mulching leaves, most leaves are reduced to disappearing fragments on the first pass, but if leaves are tougher varieties or leaf cover is especially deep, they may require two passes."

Stucky also points out that mulching and collecting can be accomplished at about the same mowing speed, depending on turf conditions.

However, Raney explains that moving slower than one would with a side-discharging mower may be beneficial when using a mulching mower. "A mulcher uses more horsepower and, depending on the turf, you might have to slow down a little because it’s holding the grass up with suction underneath the deck," he says, adding that with a mulching deck, blades have more to do and moving slower provides them the time they need. "But if you move too fast with a catcher you can get clogged up and that’s no good either."

Raney also points out that this is not to say that mulching decks are clump-free. "If you are mowing straight ahead, you’ll be do fine, but when you stop, they have a tendency to drop a big green donut," he says, adding that one more pass with the mower is usually enough to break up the clump and redistribute the clippings with less density.

Raney estimates mulching to be about 10 to 20 percent faster than bagging.

"There’s also time saved when mulching because you don’t have to empty a collector periodically," Stucky says. "Also, fewer inputs are required to maintain the health of the lawn when using a mulching mower because moisture, nitrogen and organic matter that might have been removed by bagging are instead returned to the turf."

THE FINE PRINT. However, mulching is not always the most appropriate way to mow. The decision to mulch often hinges on climate, location and customer preference. For instance, Stucky reports that damp conditions require a much slower ground speed, hence mulching in wet conditions is generally a bad idea. "It’s best to mow later in the day so that dew has dried," she says.

In fact, in some regions mulching is significantly more difficult during the spring. "In April or May, you’d have to be mowing every three days to keep up with mulching," Raney explains. "But in hotter conditions, like in June and July, when the grass doesn’t grow as fast, mulching is great."

"What the customer expects is important too," Raney continues. "If you’re doing a really nice pristine property – for example, a million dollar home whose owner wants the yard to look immaculate – mulching might be a risk. Personally I’d catch in a situation like that rather than have them be upset because there were little clumps in places where I turned or little sticks and leaves that get by without being completely mulched."

Raney believes that the popularity of mulching technology has leveled out over the past few years. "About five years ago, there was kind of a surge towards mulching and there was a lot of activity among manufacturers to have dedicated mulching decks available." He points to sporadic use across the U.S. map as one reason that mulching popularity has plateaued so quickly. "Here in Kansas they still do a lot of catching because we don’t have a problem getting rid of the clippings," he explains. "Certain other parts of the county have problems with that and have to pay to dump clippings. And there are some contractors who have their own land where they dump their clippings and then turn it over and into top soil."

He also points out that there are some regions of the country where manufacturers simply cannot sell a mower without a catcher. "There is a lot of catching in the northeast. We rarely sell a lawnmower in Connecticut without a catcher," he asserts. "Florida on the other hand doesn’t seem to do much catching at all. They have different kinds of grasses and tend to cut their grass higher – sometimes at up to 4 inches tall. Mulching in those conditions is not difficult because there is a lot of area for that grass to fall between the blades."

Raney points out the cold hard fact that catching will always look cleaner and more aesthetically pleasing than mulching, but that mulching is, cosmetically, the next best thing. "That’s the whole point of the mulching mower – to get a finished appearance that resembles catching without the labor and without stripping the turf of extra nutrients."