People have had threads on here in years past about changing colors of plants by doing the cutting and placing in dyed waters. The consensus was it hurt the overall smoke and flavor. As for extracts, have you ever tasted vanilla extract? Try it and then tell me if you think it'll be good. It's more an aromatic thing that needs to be supplemented with sugar to work.
I would think that it would have some sort of effect on the flavor or scent if the roots are taking these flavorings up. Sure, you would still have the original scent/flavor but wouldn't it create just a little bit of a different flavor? It's just like humans, our scent can change due to the items we eat and how much of it we eat.
The scent of humans is a waste product and hormonal secretion. Peace
But don't you think that the scent of plants is due to the same thing? Buds are flowers, and flowers emit an odor in order to attract a pollinator, either a bee, moth, beetle, bird, etc. When the flower is mature enough for pollination then it starts to increase it's smell, hence hormonal secretion. Also, have you ever heard of Vidalia Onions? Sure, onions taste like onions, but Vidalia onions have a slightly different taste than one that is not. Some people tried growing Vidalia onions in different parts of the country, but their onions didn't taste the same as the ones from Georgia. They eventually figured out that the reason they taste different is because of the soil that they are grown in; which that particular make up of soil was only found in that certain part of Georgia. That right there shows that plants CAN take on different tastes and smells due to their growing environment. Sure, the difference may be slight, but it's there and if it can happen with onions why couldn't it happen with all other plants? After remembering this I have kind of answered my own question lol. If you can find a liquid extract that isn't harmful then I'm pretty sure you can slightly alter the flavor and smell of your bud.
That is true Kingrow, like you said, if it was successful in any way we would have heard about it by now. Atleast I hope we would have heard about it. Maybe it's just something that people have done in the past and it worked, but it didn't hold like some fads do. Maybe in those days people didn't want buds to taste like cheese burgers lol. But who knows, I think it's plausible, as you said, plants will absorb certain properties of their grow medium, as well as other things that would change the flavor some or maybe the scent, but maybe it's just not strong enough to be very distinguishable.
Have you heard about jarring your weed with citrus peels by chance? It's supposed to impart a little of the scent anyway.