
Howdy homies! ... I'd have to agree about the general tendency of Walt (and to a slightly lesser degree SODK) being touchy on nute's, N in particular,...mine showed to be so, even with organic (GO Box),... which had me wondering about some things, and this thread queued them up again,... some big picture thoughts: true, not all leaf curl is N-tox related, but I believe the strong
tip only curl is almost always caused by it; other curling, that affects more or less the entire leaf, accompanied by that odd downward cupping/bowing, can be caused by other things besides N-tox-- environmental, (?)other nutrient issues, physical damage/malformations that grow out funny like that,...I wish I knew exactly what is behind the curling at the cellular level, causing the curl, but I'm thinking it's uneven cell division/growth between the tissues and conductive/support vessels...Nor do I know what form or where precisely the extra N is stored... I can't be sure about genetic propensity either, having never seen a plant do the curl consistently leaf to leaf for it's life,..have any of you guys? ... other swirls of consideration: the specific type of N source, nitrate (NO3-) or ammonium (NH4+), and how each is very different in terms of how they are absorbed and metabolized by the plant, soil vs. foliar too,...and what ratio they are in the various fert's, may have some impact of propensity for causing tox' issues,.... my understanding is that many plants (annuals I assume, at least) can potentially absorb and store nearly all the N they'll need well before blooming, part of the reason why bloom formulations go so light on N...but because we "farmers" are really pushing the nute's during bloom, blowing up the flower mass so much, the continued little extra N is needed to support the metabolic and physical building blocks,...and other variables dealing with how much N the plant was able to stash away! One thing about NO3-, plants will take it up and store it automatically, regardless of need, or
lack-of, even to the point of damage; I don't think NH4+ is treated the same, though both are readily taken in by the plant,... NH4+ seems to be most immediately available... energetically, nitrate is more costly to assimilate, needing to be transported to the leaves for reduction to NH4+, and further reaction with sugars; NH4+ is metabolized right at the roots, but sugars do need to be transported down from the leaves for further assimilation, but I
think it's less energy costly to move neutral charge molecules around than charged ones,... Seems temperature makes a significant difference too, in terms of which source generally works better: at higher T's, less NH4+ is best because it's assimilation needs more O2 and sugars, which are less available during high respiration times, which burns a lot of both!... at lower T's, ammonium works better because ultimately more O2 and sugars are available (slowed respiration) at the root level, and nitrate transportation is reduced by low temps,... So, all this said, I'm wondering how much influence each persons nutrients/N sources, and temp's, are coming into play here, combined with Walt's touchy palate! Of course, pH plays a big role, and the source of N makes a major impact on this... nothing goes into a cell without something going out... it's how the cells maintain both electrical and pH balance,... note the charge differences of these two; when NH4+ goes in, an H+ ion gets booted out, and we all know what that does for us! ...For NO3-, it's a bicarbonate (HCO3-) that gets booted, our #1 buffering mineral component, raising pH around the root zone,... yet another wrinkle to factor in!

..pardon the treatise guys, but you are all superior growers, and have the chops to chew on this info and figure it into issues with Walt, and your respective experiences with it,... and any other nute-pissy plants, of which there is a lengthy list,...

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Bromeo, one thing I liked about the Dyna-gro Foliar is that is has a higher NH4+ content than most all the other grow ferts I've seen, save

Grow Big which is about 50/50.... I'm speculating these two will better better for me as an OD grower, considering the higher T swings the plants experience,...
Rhyce, what nutes are you using?.. I know
Marga' is GO Box wizard! How much T swing do you guys have with your plants?...