Well obviously someone you know smokes weed and they dropped a seed or threw a seed out not thinking anything of it and it grew. It didn't just magically grow from nothing. Or maybe someone you don't know was playing a joke and they are going around spreading 420 love and planting random marijuana seeds at different locations. Who knows or maybe your wife is fucking another man and he planted the seed...the possibilities are endless...can you tell the sex of the plant? And then I kind of get the feeling you are bullshitting and you did plant the seed but because of legal issues and being paranoid you keep denying as to throw ppl off. either way it's a nice plant hope it's a female, if it is, it's a keeper. Also that appears to be more than one plant.