Which is greener, bagging your grass or leaving your clippings there?

Image Gallery: Green Living Grass clippings account for up to 20 percent of household solid waste collections every year. See more green living pictures.
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To bag, or not to bag, that is the (clichéd) question. Once the weather begins to heat up, lawns put on their bright green coats, and the familiar sound of the lawn mower fills neighborhoods across the land.

Then there's the aftermath. Bags upon bags of heavy, sweating grass herded to the bottom of driveways to await the garbage man. This unwieldy waste comprises up to 20 percent of the solid waste collected in the United States every year [source: Colt, Bell and Johnson]. A single acre of grass yields three tons of clippings using up around 260 bags each year [source: Connecticut Department of Environmental Protection]. That's why many states have banned grass waste from landfills and require that you bag them separately from your garbage.


Does that mean that not bagging your grass is better for the environment? What harm could a little grass do at a dump?

Bagging grass consumes far more energy, if you think about the waste from making the grass bags and transporting heavy loads to the dump. Once they get to the landfill, the nutrients that could go back into the soil are totally wasted. The minerals and any pesticides used to treat it decompose and eventually seep into groundwater supplies [source: Colt, Bell and Johnson].

On the other hand, if you keep your grass clippings, you can turn it into a natural fertilizer, mulch and soil additive to enrich your lawn. Many agricultural experts recommend following a "Don't Bag It" program, originally designed in Texas, to exploit the benefits of allowing clippings to fall to the ground. Because of benefits like these, Americans composted 20 million tons of yard waste including grass clippings in 2006 [source: EPA]. These lawn maintenance steps can save you time and money and leave you with a healthier, more attractive lawn.

Does it sound too good to be true? Read on to the next page to find out how you can green your lawn, both figuratively and literally, by saying good-bye to the bag.



Don't Bag It!

Longer growth means less watering because the roots absorb moisture more efficiently.
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If you think not bagging your grass entails more work, think again. Although you'll need to mow around every five days to follow the "Don't Bag It" program, it will actually cut your work time by up to 38 percent [source: Colt, Bell and Johnson]. Depending on the type of grass in your lawn, you'll generally let it stay between 2 and 3 inches high (5 to 7 centimeters). That means, you'll want to avoid using the lowest cutting settings to ensure that you do not remove more than a third of the blade at a time to promote healthy growth.

But before you get to cutting your grass, you may be wondering if you need a new lawn mower. Even if you have a grass catcher attachment on your mower, it will probably work fine if you remove it. However, consult your owner's manual or speak with a lawn-mower repair person to confirm that.


If you're in the market for a new mower and want to go bag-free, check out the old-fashioned push mower or an electric mulch mower. Push mowers may demand a little more muscle power to get it across the yard, but will usually cost less than a mulching model. Mulching lawn mowers are made with an extra blade that chops up the grass more finely before releasing it onto the ground [source: Colt, Bell and Johnson]. That promotes decomposition to allow the nutrients to reach the soil faster.

Speaking of nutrients, what does the grass recycling give back to the lawn? Because of the nitrogen, phosphorus and potassium in grass, this byproduct can provide up to 25 percent of the fertilizer your lawn needs [source: Colt, Bell and Johnson]. The healthier your grass becomes, the less water it needs because its roots absorb it more efficiently [source: Fresenburg and Starbuck].

Some people fear that leaving the clippings promotes the formation of thatch. Thatch refers to a layer of organic matter made of partially or un-decomposed bits of grass plants that chokes out new growth [source: Fresenburg and Starbuck]. According to the Environmental Protect Agency, since grass clippings are made up of 90 percent water, they break down quickly and do not contribute to thatch build-up [source: EPA]. However, if you have a layer of thatch a half-inch thick (1.2 centimeters), collect your clippings and use them elsewhere in your yard.

Where else can you use them? You can incorporate cut grass into your composting pile. Their nutrients will feed the health of the compost. Similarly, you can sprinkle it around plant beds or along landscapes as a mulch to fortify and protect it from water erosion. If you're growing a summer vegetable garden, you can mix the grass in with the soil as a natural fertilizer for the plants as well. If you have treated the grass with any pesticides, only put it in the compost since the lingering chemicals can poison the other plants.

For more lawn care tips and tricks, plow through the links on the next page.


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More Great Links

  • Colt, W.M.; Rynk, R.; Bell, S. and Johnson, W.J. "Don't Bag It!" University of Idaho College of Agriculture. (May 30, 2008)http://info.ag.uidaho.edu/Resources/PDFs/CIS1016.pdf
  • Connecticut and Massachusetts Departments of Environmental Protection. "Don't Trash Grass!" Update Nov. 26, 2007. (May 30, 2008)http://www.ct.gov/dEP/cwp/view.asp?a=2718&q=325364&depNav_GID=1645
  • Environmental Protection Agency. "Give an Inch, Save a Yard: Grasscycling and Mulching." Updated Sept. 7, 2007. (May 30, 2008)http://www.epa.gov/compost/grassmulch.htm
  • Fresenberg, Brad and Starbuck, Christopher J. ""Don't Bag It" Lawn Care." Missouri University Extension. (May 30, 2008)http://extension.missouri.edu/explorepdf/agguides/hort/g06959.pdf
  • Wilson, C.R. and Koski, T. "Eliminate Grass Clipping Collection." Colorado State University Extension. Reviewed April 2004. (May 30, 2008)http://www.ext.colostate.edu/Pubs/Garden/07007.html