Sheet Mulch

Inventory

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Tools & Equipment

• Hose - for watering the bed
• Pruning Shears - for trimming plants
• Shovel - for transporting soil
• Spading Fork (optional) - for transporting bulky items such as straw, mulch, etc.
• Tarp (optional) - for mixing soil
• Wheelbarrow or cart - for transporting soil

Ingredients

• Cardboard/Newspaper: flattened cardboard or newspaper. No glossy items
• Finished Compost
• Top Soil
• Browns (optional): shredded or whole leaves, straw, hay, wood chips, pine needles, sawdust, corn stalks
• Greens (optional): fresh grass clippings, kitchen scraps, composted manure, green leaves, coffee grounds, alfalfa meal, etc.
• Mulch: straw, wood chips, pine needles

Instructions

Sheet mulching is best done in the fall so the layers have time to decompose and settle over the winter. However, it can be set up and planted at any time of the year.

Prepare the Area

Cut down all of the vegetation in the area with shears. Don't remove it or pull up roots—just cut and drop. It will decompose in place. If the area is not moist, spray it with water and allow it to soak in before proceeding to the next step.

For clay soils, use a spading fork to create holes for better aeration. Don't turn the soil, just loosen it.

Soil Amendments (optional)

Add a thin layer of nitrogen material and/or soil amendments if desired—just a sprinkle for concentrated amendments or an inch-thick layer of bulky green items such as grass or garden clippings.

See modifications below on possible amendments

Weed Barrier Layer

Add a layer of flattened cardboard or newspaper in the garden area. If using cardboard, overlap boxes by 6 inches. If using newspaper, make layers 1/8" - 1/2" thick. Spray cardboard or newspaper as you lay it down to prevent them from blowing away.

Nitrogen Rich Layer (optional)

Add a thin layer of nitrogen-rich materials or amendments to the weed barrier.

This layer isn't necessary to create an effective sheet mulch garden bed, but it will boost microorganism and worm activity in the uppermost layers. Some options here are grass clippings, manure (if you are planting right away, use composted or aged manure), kitchen scraps, green leaves, or any of the nitrogen sources listed above.

Carbon Layer (optional)

Create a 30:1 carbon-to-nitrogen layer that will break down over time and continue to feed the garden. Make this layer about 8-12 inches thick. Spray this layer with water until it has a wrung-out sponge consistency.

Also optional but should be included with layer two. This adds a layer of bulk and helps balance the decomposition of the nitrogen below. Contents with weed seeds are not a concern here as they will be more likely to rot than sprout. It's crucial to maintain a proper balance of Carbon and nitrogen at approximately 30:1, respectfully. A pile with too much carbon can become anemic and rot very slowly.

Seedbed Layer

Add 2-4 inches of compost or a garden soil mix.

Mulch Layer

Add the final layer of mulch using seed-free materials such as straw, bark, wood shavings, etc. Make this layer 2 inches thick.

Planting

To plant in this garden bed, push the mulch layer aside and plant into the seedbed layer.

Maintain

Plants may deplete soil nutrients over time. Topdress the bed with compost, aged manure, or organic fertilizers. If the bed becomes compacted or nutrient-poor, consider reapplying the sheet mulching layers every few years.

Modifications