Click here for an updated version.
See also the World Chart of Cannabis Use.
The darker red areas show where cannabis smokers (or as they call it ‘level of abuse’) are more than 8% of the population.
The data is relatively recent (2006-2007) and clearly shows that the US, Europe and Australia love their weed! (or hash)
If you want to grow some weed see where to buy cannabis seeds online here.