Depends on the strain. Most will not put out a full blown "stench" until late in flowering (budding). Some, however, smell VERY strong even early in the veg state. Also, some do not put out much smell at all regardless of the stage of development.
yeap... thats says it all.... current strain Im growing is stinky from the start. as it is a skunk fam. my indy mother is low smell..