Well, a key thing is actually GETTING flowers (Who'd have thought right?). So make sure to always try and reference the flower thread and travel run side
http://www.torn.com/forums.php#/p=threads&f=10&t=15907728&b=0&a=0 http://travelrun.torncentral.com/ Assess what be best for you in terms of the time you have available or not when it comes to determining where to go
Then it's a case of upgrading your carrying capacity and flight times
A private island with airstrip (and you'll need to hire a pilot) is basically a must. That will add 10 items to your travel carrying capacity and reduce flight time by 30% (Other options to reduce flight time are WLT stock benefit for -50% and business class ticket for -70%, but these aren't really financially viable options for flower running, especially BCTs... as they cost more than you'd ever make on a single trip...)
Cumber faction upgrades - each upgrade adds 1 to your capacity
Suitcase - Small/medium/large suitcases add 2/3/4 to your capacity respectively (You are limited to just one of these)
Company specials - The 3 star cruise liner special will upgrade your capacity by a further 2