you kaint.......there are tens of thousands (more?) types of strains....people will guess.....chunky buds from indica......lighter/airy buds filled with hair from sativa........short and stocky plant features for indica...with maple leaf type leaves....long branches and and leaves with long thin fingers... for sativa...... most plants are hybrids.... a mixure of the two......once you get used to looking at plants you can tell the two apart very easily and maybe even pick out the sativa/indica attributes in a hybrid......i'm just starting so i don't know how to do that myself....
google sativa.......google indica..........it's good stuff to know even if you're just going to smoke pot and not grow it........so you can say....ooooooo..... yeah.... that's an indica... i wasn't expecting that....
pot is so freaking amazing.... people are like POT IS EVIL.... but there are so many different types of pot....... and they all do different stuff..... pain killer.... sedative...stimulant..... anti-depressant.... and it can be grown....and once you start growing it you don't need to buy anymore....no wonder the pharm companies don't like it..