There are quite a few folk I have met who suppose plants have brains. The problem with that is not the assertion itself, but the "supposing." The general statement is that they "think" plants can think, or are at least conscious.
They think. Or suppose. Or imagine, without a pause to profess any evidence or show interest in any.
Shallow thinking like that worries me intensely. Plants are a mystery, but the first step to unlocking some of those mysterious codes lies in not projecting human or animalistic attributes onto them. There are pertinent questions, such as why roots from trees seem to 'know' how to avoid each other, or find the best direction to go - mostly, though further, even more surprising studies show trees actually not being able to adapt when moved to new locations, and growing in a manner they might in their original setting.
But the first step must remain the same: if we are to discuss the idea that trees might be aware of their surroundings, we must first discount the idea of a brain in any animal sense.
why does the rose
emit such a beautiful fragrance
that makes her bend down
and touch petals to her nose
so I admire her sexy behind?