What Is the Difference Between Compost & Potting Soil?

Compost and gardening soil are hard to distinguish from one another. Gardeners generally use potting soil when starting seedlings or growing plants inside of the home. Compost is favored in the garden to add nutrients to depleted soil. Pick up a hand full of the two materials and the texture determines the difference between compost and potting soil.

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Compost and potting soil have nutrient-based differences.

Compost Process

Compost is a nutrient-rich soil with medium density. It is naturally made by elements including oxygen, bacteria, water and organic materials. Green matter, such as food products, and lawn clippings, and brown matter, including twigs and dry leaves, are combined to deteriorate in the composting process. The materials compost and break down into a rich soil, which is predominantly used in the springtime.

Compost Benefits

Composted materials consist of organic nutrients added to existing garden soil, flowerbeds and plant containers. The material benefits the soil with microorganisms, loosens clay for healthy root penetration and aids in water retention. Composting reduces landfill waste, such as eggshells, fruit and vegetable peelings along with leftover foods. The nutrient-filled matter reduces the use of chemical fertilizers and soil amendments.

Potting Soil

Potting soil consists of a mixture of peat moss, ground-up tree bark and tiny pieces of perlite, which is volcanic glass. The lightweight materials provide an airy growing medium for seeds and root systems. Steam-heated to kill any bacteria or disease, potting soil is sterile for added protection for young plants. It lacks nutrients and minerals. The gardener will use periodic doses of fertilizer to potting soil.

Sources

Potting soil is sold by commercial distributors throughout the year to provide a gardener and homeowner with the growing medium. Compost is sold mainly during the growing season. Composting facilities also sell the material by the pick-up load. Home gardeners compost garden, lawn and kitchen refuse using homemade or purchased composting bins. The gardener can process a home-style version of potting soil by combining garden soil, perlite and compost in a container to be sterilized in the home oven.