advice please

theres this spot i know where some marijuana of some sort grows, its in iowa. It grows under these pine trees in the country and i frequently visited them this summer and watched them grow but never saw nugs so i was dissapointed, then one time i went and they all seemed to die out....is there any way that i can let them grow for like 4 months outdoor so that they get to the size they were when i saw them and then homegrow them the rest of the time or do something out there to help them grow>?

some advice would be great thanks