I may be relatively new here but i recall going over the original question proposed in this thread in a plant bio class i took. Here goes my understanding of the subject.
There is much speculation as to which hormone actually causes plants to flower. However the most common belief is that the hormone florigen is primarilly responsible as first described by Mikhail Chailakhyan in 1937. Long story short the experiment conducted involved grafting two plants together. Plant A was exposed to the correct photoperiod for flowering and Plant B was not. The result was both plants flowered therefore proving that the hormone to flower was transfered from one plant to another through the vascular tissue. My point is that if florigen could travel between grafted plants then it could travel from one part of a single plant to another part of the same plant so long as some of the leaves were exposed to the correct photoperiod for flowering. In light of this theoretically a series of plants (5 for example) grafted together should flower even after all the leaves were trimmed off except for those of one plant. If that plant was put under the correct amount of light to flower then the rest should also flower
Additionally other experiments were conducted between different species of plants in which the same experiment was used that i mentioned above. As in the original eperiment both plants flowered. This showed that florigen was a universal flowering hormone in most if not all plants. This then brings up a question. What if a cannabis was grafted to another similar plant but another species. Would the cannabis plant flower if it was not exposed to correct amounts of light/dark to flower if the other plant of another species of plant was exposed to its correct amount of light/dark?
Once again this is just my understanding of the subject and if i have any of that wrong feel free to say so.
pce