Mulching 4 - Applying Mulch

1. Do not apply mulch directly in contact with plants. Leave an inch or so of space next to plants to help prevent diseases flourishing from excessive humidity.

2. Remove weeds before spreading mulch.

MULCH MATERIALS
Material	Amount to Apply	Notes
Bark mulch	2-4 inches	Smaller chips are easier to spread, especially around small plants. Excellent for use around trees, shrubs, and perennial gardens. When spreading mulch around trees, keep the mulch an inch or two away from the trunk. A couple inches of mulch is adequate. There is no need to apply the mulch 6 or 8 inches high, as often is seen.
Wood chips	2-4 inches	Similar to bark mulch. If using fresh wood chips that are mixed with a lot of leaves, composting may be beneficial.
Leaves	3-4 inches	Best to chop and compost before spreading. If using dry leaves, apply about 6 inches.
Grass clippings	2-3 inches	Thicker layers tend to compact and rot, becoming quite slimy and smelly. Add additional layers as clippings decompose. Do not use clippings from lawns treated with herbicides.
Newspaper	1/4 inch	Apply sheets of newspaper and cover lightly with grass clippings or other mulch material to anchor. If other mulch materials are not available, cover edges of paper with soil. Applying on a windy day can be a problem.
Compost	3-4 inches	Excellent material for enriching soil.

Bark mulch and wood chips are sometimes used with landscape fabric or plastic. The fabric or plastic is laid on top of the soil and then covered with a layer of bark chips. A caution to this practice: while initially the plastic or fabric may provide additional protection against weeds, as the mulch breaks down, weeds will start to grow in the mulch itself. The barrier between the soil and the mulch also prevents any improvement in the soil condition and makes planting additional plants more difficult.

Courtesy of the U.S. Department of Agriculture.