i've read books about lunar cycles and gravitational pull, and authors pointed out that cultures throughout time have planted, harvested, propagated, fertilized plants based on waxing/waning/full/new moons. and then obviously during winter months there are other factors in play wrt the position of the earth in relation to the sun... i think it's possible, in fact highly likely, that there are patterns and cycles that all plants follow that we will never know about since we are a completely different kingdom of creatures. i actually quite like that.