well you nailed it...it does differ from strain to strain. without knowing what type of plant you have, you can look for some general clues. such as, is the leaf wide and the node spacing close? you probably have a mostly indica variety which should stay relatively short and bush like. if youi have a thin leaf with long spaces between nodes, you probably have a mostly sativa variety which can get rather tall and lanky. keep in mind these are generalizations and not aet in stone. also, particular starins can stretch considerably during flowering...sometimes growing to 1.5X their vegitative stage growth hieght.