Sheet Mulching

Sheet mulching is a bit like making a low, flat compost pile. It allows you to build low maintenance, no-dig garden beds that are useful for growing annual vegetables and herbs. Larger trees and shrubs are best planted directly into the soil and spot mulched, as shown below.

Spot Mulched Tree

Like a compost pile, you build up layers of organics matter, alternating between green (nitrogen rich) and brown (carbon rich) materials. What is used for each layer depends on what you have available in your area - if you live near the beach it might include seaweed, if you live near a farm it might be sheep manure. Autumn is a great time for sheet mulching to make use of all the fallen leaves. An example showing how to build up the layers is below.

Sheet Mulching Example

What you Need

  • Newspaper or Cardboard
  • Water-holding wheelbarrow or large container
  • Selection of 'green' plant material: E.g - Non-seedy weeds, leafy prunings, spray-free grass clippings, etc
  • Selection of non-seedy 'brown' carbon rich materials: E.g. - Straw*, old leaves, composted bark mulch, etc
  • Animal manure or 'blood and bone'
  • Compost
  • Good optional additions include rock dust and lime
  • Water
*Handy Hint: Leave straw in the chicken run for a couple of days so the chickens can remove most of the seeds before you use it!

Chooks removing seeds from straw

What you do

There is no need to dig or prepare the soil. If you are making the garden directly on top of a lawn or a weedy patch, just chop the vegetation down and leave the cut leaves on the ground.

Covering the lawn with newspaper

Soak the newspaper/cardboard in the wheelbarrow/container. Newspaper soaks up water fairly quickly, cardboard may take longer. Cover the entire garden area with overlapping layers of newspaper (around 10 pages thick) or cardboard. Aim for about 20% of the sheets to overlap the pervious layer.

Soaking newspaper in wheelbarrow

Build up alternating layers of mulch materials on top of the paper/cardboard. Try to spread the materials evenly over the entire bed. Water as you work to make sure that all layers are thoroughly moist.

Speading the layers

Finish the bed with a 5cm layer of straw or fine bark mulch. This helps to reduce the likelihood of weeds germinating and protect the worms and microbes in the lower layers.

Liberated Lawn

Seedlings can be planted directly into the bed with a handful or two of compost to get them started as the other materials begin to break down and release their nutrients.

Sheet Mulch the whole front lawn

The picture above shows how a front lawn can be sheet mulched to create an attractive and productive food garden. If you'd like to see the real thing, look over the front fence at 27 Duke Street.