Sheet mulching

In permaculture, sheet mulching is an agricultural no-dig gardening technique that attempts to mimic natural forests' processes. When deployed properly and in combination with other permacultural principles, it can generate healthy, productive, and low maintenance ecosystems.

A model for sheet mulching consists of the following steps:

1. The area of interest is flattened by trimming down existing plant species such as grasses.

2. The soil is analyzed and its pH is adjusted (if needed).

3. The soil is moisturized (if needed) to facilitate the activity of decomposers.

4. The soil is then covered with a thin layer of slowly decomposing material (known as the weed barrier), typically cardboard. This suppresses the weeds by blocking sunlight, adds nutrients to the soil as weed matter quickly decays beneath the barrier, and increases the mechanical stability of the growing medium.

5. A layer (around 10 cm thick) of weed-free soil, rich in nutrients is added, in an attempt to mimic the A horizon.

6. A layer (at most 15 cm thick) of weed-free, woody and leafy matter is added in an attempt to mimic the forest floor or O Horizon. Theoretically, the soil is now ready to receive the desirable plant seeds.

Sheet mulch has important advantages relative to conventional methods:

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