Lucas Green wrote:The biggest flaw as it stands is I think the lack of airflow through the cardboard. Oxygen is as critical for roots as anything, i'd imagine you want to puncture the cardboard sheets at the very least.
Mike Jay wrote:Nifty idea Hisham! I'm not sure how healthy the ingredients in cardboard are. I use it myself for mulch but just one application. If it's being reapplied each year and tilled in, I wonder if the repeated application of those components would be a concern? I'm thinking of the inks and glues and things that aren't cellulose...
Chris Kott wrote:It's an interesting thought, though not without its' issues.
I see the use in making a cardboard slurry paper mat for this application, but I don't think it's the best material for the application. I prefer the idea of using woven reed or other biomass mats as a mulch layer, but in an urban environment, especially if we're talking about cardboard contaminated with relatively clean food waste, like pizza boxes and the like, it might be the thing to do.
My concern wouldn't be the adhesives as much as the inks. To combat the ickiness of either, I would include mushroom spore in the slurry specific to the soil needs. I would also consider seed for a range of low-growing living mulches that could likewise be added to the slurry in the sheet-making process, to dry out and be stored dry until application on the soil, when regular watering and weathering would cause the mulch layer seeds and fungal spore to germinate.
The living component of such a mat would first anchor it to the soil with thousands of tiny roots, it would also accelerate its breakdown into soil.