That's a good post, a man after my own heart, I totally get that and I have discovered quite often that common knowledge is wrong, there is nothing like knowledge gained first hand, you can have the whole world rail against you, but once you seen it and done it and you know something is correct then that all that matters. I'm also going to be using my mini grows to do different nutrient checks.
The different shaped fabric bags idea, came about because I was wondering why the one litre pyramid is so good, how what does it do differently and after noticing that if the root tips emerge from a slightly larger hole in the side of the pyramid, then it it completely covered in that superfine downy fur that roots in rude health get. Then it suddenly dawned on me what is special about these plugs that'd different to soil and that is that all those tiny holes in the pyramid would be all through it, and they do not collapse, you can move it around or flush it out with heaps of water if you like and you do not disturb the superfine hairs.
Then I though and what good are the hairs, well they would increase the efficiency greatly, so that must be why the plant does not seem to be limited by the size of the roots that it can form, because if you tried to grow in a one litre pot, you could grow a nice little auto but you'd expect it to be pretty tiny.
So at first my initial thoughts on the fabric bag is that it requires bigger space for the roots because it is less efficient, so I'm thinking how to get that efficiency into a soil mix. How can you make soil more physically stable. I was thinking some sort of insert into the bag like a firm plastic mesh at the bottom with a spindle and then you have two or three flat mesh discs like records that go over that, and as you fill the bag up you place another plastic mesh disc on. This would just be a starting point, may or may not be practical. Then I was thinking what about if you could, after mixing your soil, then mix some sort of binder into the soil that kept it all in place, sort of like the binder they use on the plugs. Whether a substance like this is possible only a chemical engineers could tell.
But these idea are not the point, the point is that doing the plugs have made me realise that there is much improvement possible in a smaller space and that maybe just maybe if one thinks about it there's something that can make that difference. So then while what I'm thinking about is how to develop that superfine root fuzz with soil. Hey here's an idea that just occurred to me, what about if there were little root sanctuaries you couple put in your pot, for example how about golf ball size hollow plastic balls with covered in holes, roots might grow into it and have that little space. All idea need a gestation period, but my gut reaction is there's some sort of mechanical think you could do to soil that would improve production. Or maybe not.
Peace.
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