Sheet mulching: create soil anywhere!
Updated: May 5, 2020
Oh our sweet sad lifeless soil! Our rock hard slab of laterite clay! Left lying nude and exposed to the sun for the last 20 years! The road ahead of soil remediation is a long one indeed. Let's talk about it.
Not even the round of cow pea and dhaincha came up that we sowed on the tail months of this monsoon. This was our first step on the path, thinking to green cover/green manure our plot in the rain fed months of July & August and turn that green manure back into the soil. We sowed dozens of kilos of different nitrogen fixing legumes, mainly dhaincha and cow pea.
It didn’t take. Nothing came up. Well, that was our soil litmus test and to our disappointment, the proof of our earth's lifelessness. Time for new approach.
There are many strategies in Permaculture for building soil — some take lots of time and little inputs, others are highly input intensive to deliver rapid results. We will apply both. The upper plot, Zone 1, is all intensive vegetable growing, we we want to build rich veggie beds that are ready to rock. Here we decided to employ a more aggressive method. Sheet Mulching.
Sheet Mulching is a popular Permaculture technique for building soil. It is input intensive but effective. Sheet mulching is essentially a layering system of different organic materials that will suppress weeds, invite in worms and microbes, and all break down over time to the final core: humus. The benefits: rapid fire soil creation. The costs: Input intensive — requires you to buy/acquire/salvage materials in large amounts (cardboard, compost, biomass, mulch, manure).
Our lower plot, which is larger and even more barren, is planned as Zone 2, for us that means food forest, fruit + timber trees, grains, and chicken run. We’re in a time-rich, money-poor stage of life and are happy to take the long and slow approach, spot composting and planting nitrogen-fixing pioneer species and hearty ground covers. (ANY ADVICE WELCOME!)
Getting all the equipment for sheet mulching was a true task, and one that taught us quickly to put aside our western expectations on timing and really get into the flow of village life. People will answer when they want; the boss is probably home having lunch, the delivery will not be on time and your workers will call an hour before and cancel. But eventually, inevitably, with new found patience, the work will get done.
We're lucky that Panchgani has recently taken pride in its waste! This is a forward thinking town that is now collecting all waste and processing it at a central point. Kunal and I took a drive up there and were very impressed with a massive compost-making process, plastic separation and shredding for road construction, and cardboard and glass separation. Quite meticulous! Kunal negotiated a sweet deal for 1 TON of compost to be delivered to us for rs. 2000 (about $40 AUD). Wow baby, coming from Melbourne, that is 2x 20 L bag at Ceres. Sweeeeet.
With a good handshake with the government waste truck driver, he agreed to deliver us the Panchgani market food scraps instead of taking them for composting. Only for the price of delivery.
Slowly, things arrived at the farm truck load by truck load and Kunal and I had some damn dirty days moving rotting veggie scraps and cow shit around.
So check it out!
Here we are, with bare land and a JCB coming through to flatten out corners of 20+ years of accumulated village rubbish. Me looking quite skeptical of this big petrol-guzzling machine on our sweet land.
After the JCB use, a generous offer from a neighbor in construction, we had to get that bare soil covered!
Next step, lay out the garden beds. Our design was already sketched out, so I went down there with a measuring tape and a big bucket of ash from the chula to mark it all out.
Sourcing cardboard and stripping off all the plastic tape. Laughed all along the way as 50% of our cardboard were Big Ag chemical company packaging for insecticides, herbicides, fungicides, and fertilizers. All with large warning labels -- POISON, DO NOT INGEST. Loved the irony of using the chemical BOXES to suppress weeds instead of the chemicals themselves :) Well done, permaculture.
Veggie scraps laid down in the garden beds and cardboard to denote the paths.
Then we topped all the beds with cardboard. This functions as weed barrier.
1 ton of dung ready to spread! Lots of heavy hard work.
With the help of 3 lovely ladies, who were pretty disappointed when they showed up for their 'gardening' work day in clean and pristine saris, we unloaded that all one bucket by one bucket.
Dung is down! Important to know we are watering the cardboard well, to the point of soaking, before laying the gober (cow dung). It is critical to water in each layer of your sheet mulch well so you can lock that water in and encourage microorganisms. Remember, dry is dead.
Our area is a sugar cane BELT in India -- farms are pumping out this thirsty cash crop like its going out of style (which, if we have anything to do with it it will be!). But that also makes it the most available bio-waste. So we took it!
Now, on top of this we need 2 more layers -- a nice thick layer of compos