In permaculture, sheet mulching is an agricultural no-dig gardening technique that attempts to mimic the natural soil-building process in forests. When deployed properly and in combination with other permaculture principles, it can generate healthy, productive, and low maintenance ecosystems.[1][2]

Sheet mulching, also known as composting in place, mimics nature by breaking down organic material from the topmost layers down. The simplest form of sheet mulching consists of applying a bottom layer of decomposable material, such as cardboard or newspapers, to the ground to kill existing vegetation and suppress weeds. Then, a top layer of organic mulch is applied. More elaborate sheet mulching involves more layers. Sheet mulching is used to transform a variety of surfaces into a fertile soil that can be planted. Sheet mulching can be applied to a lawn, a dirt lot full of perennial weeds, an area with poor soil, or even pavement or a rooftop.[3][4]

Technique

Typical layers of natural soil.
Typical layers of natural soil.

A model for sheet mulching consists of the following steps:[1][3]

  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 surface soil, or 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 or transplants.[5]

Variations and considerations

Advantages

Sheet mulch has important advantages relative to conventional methods, such as tilling, plowing or applying herbicides:

Disadvantages

See also

References

  1. ^ a b c d e f g h i Elevitch, Craig; Wilkinson, Kim (1998). "Sheet Mulching: Greater Plant and Soil Health for Less Work". Agroforestry.net. Archived from the original on December 10, 2002. Retrieved November 9, 2011.
  2. ^ Mason, John (2003). Sustainable Agriculture (Second ed.). Collingwood, Vic.: CSIRO. ISBN 978-0-643-06876-6.
  3. ^ a b c d e f g h Hemenway, Toby (2009). Gaia's Garden: A Guide to Home-Scale Permaculture (2nd ed.). White River Junction, Vt.: Chelsea Green Pub. ISBN 978-1-60358-029-8.
  4. ^ "Organic Mulch". Saturday, 23 January 2021
  5. ^ Stout, Ruth (February–March 2004). "Ruth Stout's System". Mother Earth News. Retrieved November 9, 2011.
  6. ^ Nicole Faires (4 May 2012), The Ultimate Guide to Permaculture, Skyhorse Publishing Inc., p. 228, ISBN 978-1-62087-316-8, retrieved 3 July 2012
  7. ^ a b "Sheet Mulching". StopWaste.Org. Archived from the original on October 1, 2011. Retrieved November 9, 2011.
  8. ^ Phelps, Dave R. (2013). "Use of Less-Toxic Herbicides and Sheet Mulching in Landscapes". 2013 CWSS Proceedings. Annual Conference. California: California Weed Science Society.
  9. ^ "Sheet Mulching from the Ground Up". Water Conservation Program. City of Santa Barbara. March 11, 2014. Retrieved May 8, 2022.