Below are the steps I take when making a layered mulch ring prior to planting trees.
1.) In the first image you see a ring of aged manure. This can be any form of organic material, compost, food scraps, organic topsoil, potting soil, etc.
2.) In the second image you see the next layer of the system, non-glossy news paper. Piling this on thickly (full sections at a time) you can create a feast that, when combined with the manure, adds fertility whilst attracting worms from the surrounding area. Feeding these worms benefits them of course, but the greater benefit is their byproducts which come in the form of castings and micro tunnels of aeration. Earth worms are workaholics, they are a non-stop source of sub-surface micro tilling with rich castings (read “POOP”) byproduct that feeds the primary tree and guilded ecosystem.
3.) In the third image you see a thick layer of cardboard that acts as a moisture retaining grass barrier. This layer also feeds the worms, but most important is its light withholding qualities. When waterlogged, this second-use resource (visit your local hardware, grocery, book, or box story for an endless free supply) holds a vast amount of moisture whilst quickly breaking down to form more soil.
4.) In the fourth and final image, you see a thickly applied wood chip layer (4″ – 6″). This layer adds even more moisture retention. Take a walk into the wild of your nearby forest. What you will see are trees whose caretaker has designed a system that provides all of the forest’s needs, water, nutrients, protection, food, etc. The trees from above drop an ever-increasing and constant supply of wood chips. Not only does this organic material soak up water and slowly release it, keeping the soil at the perfect moisture level, it provides a continuous supply of micro nutrients in the form of minerals that support the ecosystems below. Add this as the final layer in your mulch ring.
Once you’ve assembled these life building systems, let them rest for a full year if time permits. If pressed for time (which I am) then set these up in the fall in preparation for spring planting. When the time is right, piercing through the saturated layers will render a prime planting environment for your fruit and nut guilds.