General question

if i start a couple weeks inside and transfer in may, in the northern us, when should the plants be done??? Ive heard outdoor grows can last 2 months some like 5.

Yeah.... you really need to bone up on your weed lore. You are in for the long haul, my friend. 5 months guaranteed, 4 months for some early strains.

UNLESS you wont to cover them up with light proof bags or bring them inside in a dark room to create the '12/12' light cycle your plant will need to flower, this has to be done with a good degree of consistency and as u can imagine would be an annoying thing to do every day for 2 months

peace.