Landscape waste that is generated from trees, shrubs and lawns can be a considerable factor for municipalities to deal with in terms of space, time and effort needed to process it effectively. On the other hand, clippings, small branches, leaves, seeds and fruits from landscape plants can be efficiently processed on site and turned into a valuable resource for property owners. In so doing, many benefits will be reaped including a reduction in landfill volume, the creation of compost that can be used to improved lawn and landscape soils and the need for extensive time to collect, bag and dispose of the materials. Overall, it just makes good sense to “leave it on the lawn”.
3 Options
In one way or another, lawn waste should be processed and left on site. Three main ways are useful to both homeowners and municipalities. First, lawn clippings can be recycled back to the turf through the use of a mulching mower.
In the 70’s and 80’s, mulching mowers were not as efficient as they are currently. Older models utilized low horsepower, a flat deck and simple cutting surfaces, which often led to the mower bogging down and leaving clumps of grass clippings and leaves all over the lawn. Over time, mower manufacturers made improvements to the deck, horsepower and cutting surfaces to increase efficiency, usually cutting and re-cutting the grass blades several times. As a result, mulching mowers have become a good tool for on-site waste reduction.
Another good approach is to pick up the grass clippings and fallen tree leaves and place them in a compost pile. When combined with vegetable waste, dying houseplants, vegetable garden plants and coffee grounds, these additions can create a valuable resource for the landscape. Materials containing fat or oil should not be added to a compost pile.
To construct a compost pile, sprinkle 4-5 inches of these materials over the top of bare soil, then add 1-2 inches of vegetable garden soil, then another 4-5 inches of green waste, another 1-2 inches of garden soil and so on until the pile is 5 feet tall. As the pile is built, soak the layers with water until they are thoroughly moist. The pile can be surrounded by timbers, deck boards, concrete blocks, snow fence or similar materials to contain the ingredients, yet allow sufficient air to penetrate to the center of the pile and start the decomposition process. Once a month, turn the compost pile and re-moisten it to speed up the process. On average, the contents will turn into usable compost in 3 months. Compost is a very valuable amendment for vegetable, lawn and garden soils; 2-3 inches or so should be incorporated at the time of planting.
A word of caution: it’s best to avoid incorporating compost into the planting site of woody plants such as trees and shrubs unless the entire landscape soil can be enriched. Incorporating compost only near the roots of trees and shrubs will cause them to preferentially remain close to the trunk instead of expanding laterally into the landscape.
A third way of utilizing grass clippings and tree leaves is to pick them up with a bagging attachment, then spreading them out in a thin (1/2 inch) layer in a vegetable or fruit garden as mulch. This method results in the suppression of weed seeds, the retention of soil moisture and eventual decomposition and nutrient recycling for garden soils. If lawns have been treated in the past 3 weeks with a herbicide to control dandelions and other broadleaf weeds, the clippings should not be used.
