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Grasscycling

Grasscycle: Leave the clippings for a healthy, easy-care lawn

Grasscycling, or mulch-mowing, means leaving the clippings on the lawn to feed the soil. Grasscycling saves time, reduces waste, reduces irrigation and fertilizer needs, and makes lawns greener and healthier. Give it a try!

The facts about Grasscycling: save time and money

Scientific trials and turf professionals have shown that mulch-mowing improves lawn health and resistance to disease. It speeds spring green-up, and lawns stay green longer during dry summer conditions because of deeper root development. Grasscycling can reduce your total mowing, bagging, and disposal time by up to 40%. No more bagging and dragging clippings to the curb!

Grasscycling doesn’t cause thatch buildup – earthworms recycle the clippings quickly to build your soil. Grasscycling can replace up to ½ of your lawn’s annual fertilizer needs, reducing fertilizer costs and water pollution. Lawns grown on healthy soil may not need any fertilizer!

You can grasscycle with any mower (see tips below). But when it's time to shop for a new mower, buy a mulching lawn mower (see shopping guide below). Good mulch-mowers blow the clippings down into your lawn where they decompose and fertilize the lawn quickly, and won't be tracked into the house. Mulch-mowers will leave a clean lawn year-round, as long as you mow every five to seven days during the spring, and slow down when mowing through overgrown patches.

Grasscycling tips

  • Mow when the grass is dry, to avoid clumping.
  • Set cutting height up to 2 to 2½ inches to hide clippings better, and make a healthier lawn.
  • Try to remove only one-third of grass length per mowing.
  • If the grass is very overgrown, mow twice: first at a high setting, then wait a few days and mow lower.
  • Mow every five to seven days in the spring. (Every two weeks may be enough in the summer.) You'll still save time over bagging and dragging clippings to the curb.
  • Water and fertilize less. Remember, every time you grasscycle, you add free fertilizer to your lawn.
  • Sharpen mower blades twice a year.

Learn more

Mulching Mower Tips
Grasscycling and Mulching Mower Guide (pdf) gives tips for successful grasscycling, and for buying a mulching lawn mower.
Natural Lawn Care (pdf) gives how-to details for complete healthy lawn care.
Ecologically Sound Lawn Care for the Pacific Northwest (pdf) 90-page manual, or the 8-page summary Sustainable Lawn Care for NW Professionals (pdf) have more information on planting new lawns, mowing, fertilizing, and maintenance for professionals and homeowners.

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Questions

Contact the experts at the Garden Hotline at (206) 633-0224 (language interpretation available) or email help@gardenhotline.org to learn about stores that sell mulching mowers, or for any lawn and garden question.