Compost is often used as a top dressing on lawns, shrub areas and gardens. While it has some nutrient value, it's greatest benefit in a home setting is holding nutrients in the soil in the root zone, making them more available to plants. New research also shows compost can help suppress some plant diseases and reduce the need to pesticides.
Compost can be used in a mix with potting soild to hold water in potted plants on decks and patios. In a vegetable garden, compost in the soil helps the soil's water-holding capacity, providing more moisture to grow crops.
The amount of compost you add to the soil will depend on the what you're using it for. Here are some guidelines:
Potted plants: 5 to 20 percent compost. A higher percentage mixture helps hold moisture in items that drain quickly, like clay pots.
Vegetable gardens: One inch of compost down to a depth of five inches by rototiller or shovel.
Flower gardens: Compost blend of 20 percent. Dress perennial flower gardens with 1/4 to 1/2 inch of compost.
New trees and shrubs: Compost blend of 10 percent.
Established trees and shrubs: dress with 1/4 to 1/2 inch of compost.
Established lawns: Top dress with 1/8 to 1/4 inch of compost and rake into grass. Best results include aerating lawns before applying compost.
Seeding new lawns: Apply 1 to 21/2 inches of compost to the surface and till well into the top 6 inches of soil. Then apply seed and rake into surface.