Hi Ballyculter!

I am certified organic, so don't use fertilizers, tho my dad and almost all my neighbours do. P is #2 in use after Nitrogen and before K (Potasium). N makes plants growthy, P and K help put seed in the head and perhaps add to plant health (extreme simplification). I think a stock like the one you mention (I seem to remember reading about it a bit a yr ago or so) will be fine if it can produce at a reasonable price. The demand for P shouldn't go anywhere really. The one real threat I see to P is that a lot of it ends up in the rivers after spring runoff, then into lakes causing terrible algae blooms (Lake Winnipeg, Killarney lake). There are other sources of problem waterborne P as well but I can see restrictions in the amnt of P that can be applied and perhaps the timing. Most soils have lots of P, but it is "tied up" and unavailable to the plant. Some products like Provide offer a biological means to help make the unavailable P in the soil available to the plants. Provide doesn't have a huge following as I dont think it is overly effective. I think it works somewhat, but most farmers wouldn't cut their P out altogether and risk it. An improved type of Provide could eat into sales of P.

I think the 2 negatives are not exactly looming problems and production costs and problems (or lack of) as well as transportation costs or efficiencies are probably where a stock as Phoscan will thrive or die as demand.

Probably didn't help, but I provided some reading!