my experience is that bigger is the pot and bigger is the plant. if you have space, put the plant in garden, will became giant!
for compost i use very "rich" terrain(i have no other words to say it ). you can conseider that plant like a strawberry .
pollinate the plant is very simple, you can use the pollen of the same plant. when you do this correctly, the top of "female reproduction thing"(ahhhhh i don't know english!!!! ) will close simillary to a dionea trap(more slower).
i have sow 10 days ago, ibicella lutea, proboscidea louisianica and proboscidea parviflora, 4 of each. the seeds have 2 years.
2 seeds of proboscidea louisianica have born yet!
bye
Piero