blitz1976 wrote:
maybe I am being too scientific but I thought it would be cool to have a list of useful permaculture style species and what there nutrient needs are.
You seem to be using "scientific" as a rough synonym for "reductionist." I think they're a good 60 degrees apart.
Becoming more reductionist can make science seem more appealing, and science often goes faster if done with a very reducitonist mindset: the two aren't completely orthogonal. But I think a major danger of cataloguing plants in a framework that only considers nutrients isn't that you'll kill they mystery of them, so much as painting a misleadingly simple picture that might be adopted by those who insist on a definitive
answer.
The catalogue you're building would be very useful, but I think companion planting is maybe 1/3 a question of nutrients. Other important issues you might want to consider in your catalogue are
root morphology and root exudates.
Some catalogues are very good about listing deep, shallow, or intermediate
roots. Also roots' ability to hold soil can be very important.
There are some famous exudates like juglone (black walnut) and ailanthone (tree of heaven) that stunt the growth of many plants and drastically limit some species' companion options, but it's also important to know about how much sugar a root system will exude to maintain the
local soil ecosystem. And there are more complicated effects of root exudates, as in the case of marigolds.
Since a lot of the science is yet to be done, a good catalogue might also have room in it for some pure phenomenology: these do well together, these don't, we're still figuring out why.
"the qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men. They are manifestations of the laws of nature, free to all men and reserved exclusively to none." SCOTUS, Funk Bros. Seed Co. v. Kale Inoculant Co.