3 frames per minute, or 1 frame every 20 seconds will give you a little under 5 minutes, but you might want to get a longer time lapse and just compress it more in post. 10 frames per minute, or 1 frame every 6 seconds will give you about 15 minutes. Then, you can just change the speed of the video to fit the time you want, just in case you want it to be longer than 5 minutes.
