I read somewhere that planispheres get updated every decade or so since the stars drift slowly, so a used one from the 90s might be a little off. Mine is from 2004 and the Big Dipper still lines up fine, so you're not alone out there.

Tried that chunky mix too and my plants hated it. Turns out the stuff drains so fast the roots dry out between waterings, so plain dirt holds some water and the plant actually drinks.

A $44 savings does not fix patchy grass, so I still hand water my front yard here on Ash Street.