Well... there is a lot of things involved in the high.
First, there is the amount and concentration of the active substances (usually THC/CBD) in the weed. As larger it it, larger the duration of the high.
The intensity of the high (level of highness) also increases with the amount of THC/CBD, but only until a certain level. Beyond this level, an increase in the amount of THC/CBD wont make you any higher, but will only make the high last longer.
Also, there is the interaction between the cannabinoids in the weed. Some cannabinoids (usually CBN/CBD) can make the THCs effects last longer, so strains rich in CBN (and sometimes CBD) will take longer to kick in ("creeper" weed) but the high will last longer.
Coelho Reviewed by Coelho on . What makes cannabis strains different? How come one strain will make you high for a few hours, and a different one only gets you high for an hour, but they are the same high level? Rating: 5