the research in that article suggests that b1 doesn't do anything to stimulate
ROOT growth, but that's not what this product is supposed to do. it was pitched to me as a "bud hardener" that will promote more intense flowering and denser buds. there were no claims that it was supposed to boost root growth. i don't believe superthrive makes any such claims regarding root growth either. not sure where that came from, but, ok. point taken.
that's not to say that b1 doesn't benefit plants.
there was sudden new root growth, which i am not attributing to b1, but the likely presence of IBA (like the article says) or other known rooting hormones in the bottle. my roots swim around outside the hydroton baskets, so i can see what goes on day to day. new root growth hasn't been visible for more than a month. three days after adding final drive, i saw nice, white, quickly growing root tips, nicely branched as well. the active root tips probably grew about 6" before stopping. superthrive also had a similar effect when i added it earlier in my grow, but, again, superthrive also has hormones, which are most likely responsible.
i don't think they're adding IBA to encourage root growth during the last few weeks of flowering. i think that is just a side effect, not necessarily a bad one. IBA is a stress hormone, so pumping it into your plants will cause a stress response that would normally be triggered by some kind of adverse conditions (too cold/hot, too dim/bright, too humid/dry, too wet/dry, not enough nutes, too many nutes, not enough DO, pruning, pest infestation, disease, etc.). stress supposedly causes the plant to freak out and do what it needs to do in a hurry, which is make more flowers to try and catch pollen so that it can create seeds and reproduce.
new pistil growth was slowing. after adding final drive, a fresh new round of pistils exploded everywhere. i know my plants and they were starting to wind down. adding final drive really made them pop one last time.
finally, the strong "vitamin" smell went away after just 24 hours or so, which suggests a pretty quick uptake. i don't think the fish would've absorbed/used THAT much b1 and they would've peed out the excess (like humans) anyway. the other possibility is that some microbe present in my aquaponic water broke down the b1, but i doubt that that's the case. i'll put my money on the plants.
so back to b1. in order to understand the benefits of b1, you need to understand what b1 does in a plant. b1 is essential to produce ATP, which is the smallest unit of energy in the plant (and your body). biology 101 stuff. if you need a refresher, google citric acid cycle, krebs cycle, ATP.
check out the abstract for this study:
https://www.sciencedirect.com/science/article/pii/S0176161711812496
soybean roots and leaves both absorbed vitamin b1. b1 absorbed from the roots were very mobile and was detected in new tissue growth. they could distinguish the b1 molecules that they fed the plant with b1 molecules produced by the plant itself or by soil microbes using something called 14C thiazole labeling: they can literally tag individual molecules of b1.
after 7 days, the amount of measured 14C labeled b1 molecules in plant tissue samples was reduced by 50%, which is no surprise, given that vitamin b1 is essential for plant metabolism. the point is, plants can actually store and use "extra" b1. while this study was specific to soy beans, all plants use ATP so all plants require b1 to function. it doesn't necessarily need to be supplemented, but it is a molecule that is very, very important to plant metabolism.
to suggest that the benefits of b1 are some kind of urban myth is, in fact, a myth in itself.
so from these two articles, here are the scientific facts about b1 and plants:
1. b1 does not stimulate root growth
2. b1 is essential for plants to survive
3. healthy plants produce b1 endogenously
4. certain soil microbes produce b1 exogenously
5. plants can absorb b1 through roots and leaves
6. b1 absorbed through the roots is very mobile
7. plants can store and utilize b1 absorbed through roots and leaves
now, surely there are folks who will say they've grown kickass weed for years without adding b1, and i don't dispute that that's the case and that is possible. like the studies say, plants are capable of producing their own b1. however, that doesn't mean that adding b1 does not have a beneficial effect, especially in hydro where there are no b1-synthesizing soil microbes. the study says precisely the opposite, that plants can, in fact, absorb and utilize "extra" b1 fed through the roots.
for me and my system and my current strain, i can report that adding a b1 supplement with hormones made my buds go crazy one last time. i think the reason you don't just add it from day 1 of flowering is because the stress hormones will work against you at a certain point, even herming out on you, just like with any kind of excessive stress you subject your girls too.
if you've got buckets going or are in soil, a side-by-side controlled experiment would be easy enough to do to prove it to yourself.
