I havent seen any perennial plants ,
but i have seen what you speak of idiit on a few plants ,
they were african sativas and would have mature and maturing buds on the same plant as vegetating branches ,
you could harvest mature parts from the plants perpetually ,
while other parts on the plant continued to grow with no flowers on them ..
I only recall 2 plants doing that of the many i grew ,
they were very appreciated though ,
one produced an ounce a fortnight or so ,
very handy .. lol ...
but i have seen what you speak of idiit on a few plants ,
they were african sativas and would have mature and maturing buds on the same plant as vegetating branches ,
you could harvest mature parts from the plants perpetually ,
while other parts on the plant continued to grow with no flowers on them ..
I only recall 2 plants doing that of the many i grew ,
they were very appreciated though ,
one produced an ounce a fortnight or so ,
very handy .. lol ...