Most short lawn clippings are best left on the lawn, where they return nutrients. If an adult collects extra clippings, they can also become garden mulch.
- Find out what was used on the lawn. Do not use clippings after a recent broadleaf herbicide treatment. Read the product label for its exact restriction; rainfall after treatment is not proof that residues are safe for vegetables.
- Skip clippings from a lawn with heavy disease or many mature weed seed heads.
- Let clippings dry, then spread no more than 1 to 2 inches (2.5 to 5 cm) at a time.
- Keep them away from plant stems and add another thin layer only after the first begins to dry and settle.
- Mix extra clippings with dry leaves or straw in the compost, rather than making a thick green pile.
Wet or deep clippings can mat together, block air and water, and decompose without enough oxygen. That is what makes a slimy, bad-smelling layer.