Hi All, I have a soil question. In all of my reading regarding soil for in containers, the concept of structure keeps emerging. As soil breaks down, or you use garden soil in a container, in compacts into a cement-like substance that roots cant grow in. So, why is it that the same soil in the garden doesnt compact like I hear it does in containers? Why does the garden, that is all dirt, not turn into a parking lot over the course of a year? Structure seems to be a bigger issue in container gardening than in regular gardening but I cant find any articles that speak to this point. I guess Im asking about the physics of soil compaction. Thank-you Michael
Potting media tend to be soilless and highly organic, so as the medium ages it degrades to muck. Inside a pot it is a smaller area of material than the ground, partly cut off from the atmosphere by the pot and completely cut off from the ground. Natural soil is often too heavy for container use, it would become too damp and airless inside the walls of a pot. I've never encountered old potting soil that had become like cement, nor can I think of a reason why that would be expected. Concreted ground, on the other hand, is not rare here in the wake of the Vashon Glaciation.
Write to Brent Walston (www.evergreengardenworks.com) who's done quite a bit of research in the area.
The tilth of soil is usually created by microbial action. and worms. and mycorrhizal growths. All of those guys do things in the soil. They create air pockets and they secrete acids and they form filaments between soil particles. and then they eat each other and do it all over again. and again but in the pots they are like rats in traps unless you give them some help. Yea?
