But....one thing I still just dont get is....WHY do new growers mess with soil at all? You can neverr know how much N,P or K is already IN the soil....so how the hell can you possibly know how much to add in nutes?
Im serious...I just dont get it.
HEMPY is the answer. With nothing BUT perlite, you can KNOW exactly what amount of of essential nutriens go into your plants. Plus, it's cheap.
I know some folks say weed tastes better when grown in soil. Whatever. I ask...do ya wanna taste the WEED or the dirt it was grown in?
Switch to Hempy----and kiss yer soil problems goodbye. NO soil = NO soil problems.
CW
Mold is not one-celled plant life. It's multi-cellular fungi. You can break up the mycelium by mixing it in, but while good conditions persist it will just re-colonize the medium. It will break down, retain and cycle the nutrients in dead organic matter, form humus and contribute to the structure of the soil. In particular fungi are necessary for digesting complex carbohydrates (cellulose, lignin, chitin) and opening materials up for bacterial decay (since bacteria can't penetrate things like fungi can). As fungi actively decay organic matter they release 'wastes' which include plant available nutrients. They also leave behind organic acids and enzymes that continue to break down organic materials and more nutrients are released when fungi is eaten by predators (such as protozoa and nematodes, some micro-arthropods).
It is easy enough to gauge how 'nutritious' a medium is once you know a little bit about organic amendments and just what comprises your 'soil' or soil-less mix. Potting soil isn't 'dirt', and most brands don't come very close to being 'soil', either, which is an important consideration. A base potting soil like the one the OP describes is really just a bare soil-less mix: sphagnum peat, perlite, and lime... not much for macro-nutrients and no humus. Humus is important for various reasons as it retains nutrients (higher CEC than peat), imparts biological activity, and aids in nutrients absorption (humic acids are organic chelates).
One of the very reasons for growing organically in soil (or soil-less mix) is to drastically reduce how much the plant depends on you to provide for it, including nutrients. You don't worry about exactly how much nitrogen, phosphorous, or potassium or any other nutrient is going in because you're really nourishing the soil, not the plant itself (not to mention that plants need many more nutrients than NPK). Instead we apply various organic amendments, many of which contain a very broad spectrum of nutrients\trace elements, and let microbes take care of the rest. The plant controls the microbes by producing\releasing exudates thru its roots, into the rhizosphere, in order to stimulate and cater to certain kinds of microbes capable of providing\assisting the plant with specific things that it needs (including certain nutrients). The various compounds plant roots exude include carbohydrates and amino acids.
Perlite doesn't retain any nutrients whatsoever (no CEC), it is totally inert and seems much less conducive to booming microbial activity, which is the foundation of good organics. The rest of what you say makes zero sense; otherwise cannabis grown in just perlite would taste like perlite. Remember, though, that potting soil simply isn't dirt. However, even cannabis grown outdoors in soil shouldn't end up tasting like dirt. Cannabis grown in healthy living organic soil may very well taste better because of the full spectrum of nutrients and trace elements it should contain, and the diversity or organisms it has providing for it, all of which contribute to the plant growing to its full genetic potential. Such a living soil shouldn't lend to any problems at all