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Residential Composting

How to apply compost

Why is compost good for your garden?

Compost amended soils are good for your garden and lawn. The best way to improve your soil is to mix in compost, to nourish plants and to feed the intricate web of soil life. Doing this will help keep the soil loose, fertile and help fight pests and diseases.

When you amend or mulch your soil with compost, earthworms and other soil life move through the compost and help carry the nutrients down into the soil. Also, laying down a layer of compost mulch around plants helps reduce weeds, reduces the amount of moisture that can evaporate and prevents soil erosion and moderates soil temperature. 

You may want to test your soil

The soil test is an excellent measure of soil fertility. The standard soil test provides the status of phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), pH, cation exchange capacity, lime requirement index, and base saturation. Additional tests are also available for iron (Fe), zinc (Zn), manganese (Mn), soluble salts, and nitrates.

Soil fertility fluctuates throughout the growing season each year. The quantity and availability of mineral nutrients are altered by the addition of manure, compost, mulch, and lime or sulfur. Furthermore, large quantities of mineral nutrients are removed from soils as a result of plant growth and development, and the harvesting of crops, and soil leaching. The soil test will determine the current fertility status. It also provides the necessary information needed to maintain the optimum fertility year after year.

If you are unsure about the quality of your soil, soil type, and ingredients it may need to become healthy, you can have your soil tested. However, this can be a costly venture. 

Applying compost

Step 1. Amend the soil before planting. Use a shovel to mix the compost with the soil before planting trees, shrubs and flowers. Amend a large area rather than a small hole to hold each plant. Recommended amounts:

Amount of compost to be tilled into each 100 square feet of planting area.

Gardens: Mix compost to 10-12" depth
Clay Soils: 16 cu. feet (0.6 cu.yd.) = 1" layer of compost
Sandy Soils: 24 cu .feet (0.9 cu. yd) = 3" layer of compost

Top Dressing for Lawns
New Lawns: Mix compost to 6" to 12" depth
Clay Soils: 8 cu .feet (0.3 yd) = 1" layer of compost
Sandy Soils: 13 cu. feet (0.5 cu. yd.)= 1.5" layer

Step 2. Mulch in the early spring to conserve moisture and prevent weeds. Mulch again in the fall to smother the weeds and retain soil temperature.

You can mulch with compost, grass clippings, or fine, medium or bulky bark or wood chips. You can apply mulch to annual or perennial flower beds, flower pots (indoor and outdoor) and trees and shrubs.

Step 3. Top Dress the Lawn by spreading a thin layer of compost on your lawn is great for the soil and builds a healthy "eco-web". This helps resist disease and reduce the need for synthetic fertilizer which may pollute the watershed.

In spring or fall when the soil is moist, use an aerator tool to remove plugs of soil or use a rake to expose the soil. Next, using a spreader tool or a rake, spread a thin layer (½ inch) of compost over the lawn. The grass should be standing up though the compost after you apply it. You can also mix grass seed in with the compost to encourage new growth.