Volunteer Marjie shares her experience of using a cardboard mulching technique in her garden.
Helena tells me that there are plans to develop another part of the garden using the sheet mulching method.
The advantage of this method is that you can create healthy, weed free soil without using chemicals, and without digging. Sheet mulching can be achieved on any scale, but the trick is to have all the materials ready and at hand so that the work can be done in one go. And it’s a really fun project too.
I’ve used a variation of this in a couple of gardens, and thought I’d share the basic steps. I based this recipe on “the ultimate bombproof sheet mulch” from Gaia’s Garden, by Toby Hemenway, Chelsea Green Publishing, 2009
You will need:
- Piles of old newspapers or cardboard (large pieces, not shiny, and with any staples or tape removed)
- Soil amendments eg lime, blood and bone, rock phostpate etc. depending on your soils needs
- Bulk organic matter – Straw, leaf mould, seaweed
- Top layer of material such as straw, leaves, wood shavings, pine needles etc
- Clear the ground of lumps (in this case I had to remove most of a layer of pebbles, but left a thin layer for drainage)
- Water the area the day before you start.
- You can leave weeds etc as the mulch will stop them from growing, and will give decomposers/worms something to start on.
- If the ground is clayey, open it up by pushing a fork in and rocking it a little. Do this across the area you are mulching. This allows better moisture and root penetration.
- Sprinkle some blood and bone over the area.
- I added leaf mould at this stage.
- Start at the far side of your plot so that you don’t stand on the wet cardboard/paper.
- Lay the newspapers or cardboard over the area making sure there are no gaps for light. Wet the sheets as you go.
- Place a layer of straw, about 8-12 inches thick, over the cardboard, damping it as you go.
- Sprinkle on more blood and bone.
- Add at least two inches of compost mixed with any available soil.
- If the area is to be left to decompose for a few months, add some manure.
- Add a layer of straw, leaves, fine bark to finish, if you want.
To start planting, I made pockets in the mulch, filled them with a handful of compost and placed the plant in the hole. As the materials broke down I added thin layers of seed sowing compost when I wanted to sow seasonal vegetables, like lettuce, radish etc. Keep the compost topped up, fertilise when necessary and within a year you will have a productive garden bed.
Blog text and photos by Marjie Spence.
The newly rabbit fenced area below the polytunnel has a large grassy area, we are in the process of converting it into a new Veg growing area using the cardboard mulching method described above (but with all composted material as mulch)