alot of plants have clever methods for spreading seeds. i think the bud is there once seeded, and laced with thc to be eaten, by birds badgers beaver, whatever. then once they ingest it and it begins to be absorbed it disagrees with them, as it is a posion after all. so then the animal now some where else throws up or shits its self, containing the seed.

this will provide moisture and fertilisation for germination and to allow the seeds to spread.