What I learned from my deadly multi-failure | Canberra Times

I had a problem. The carrot grows only as long as the palm of your hand, and has interesting shapes that stop and bend. Ground spuds spread tubers outward instead of downward. So it had to be mulched all the way to the top leaves to get a decent harvest. Shallow-rooted vegetables like lettuce worked well, but even tomatoes seemed to have difficulty pushing their roots through the newspaper walls into the soil below. At that time, the newspaper was still mostly intact, with two types of soil: shale above and shale below. Newspaper, or cardboard, or in the worst case, old carpet, form a barrier between the microorganisms in the soil and what lies above. Damage.