Question
I have a perrenial vine that has huge heart shaped leaves (like a morning glory/moonflower) but much larger, up to 12".  It is a rapid grower and hardy in zone 5 and will go over 25' but it does not flower.  It is a twiner and has been in it's location for about 20 years.  Any insight you can offer would be greatly appreciated.  I want to propogate a cutting of it for the children who grew up here as it was their mother's plant and they love it.  

Answer
Hi Nancy,
Thanx for your question.  It sounds like Aristolochia durior (Dutchman's pipe) and the flowers are difficult to find.  I have not however, found a leaf as big as 12 inches.  I've seen 6-8 inches but not 12.  This plant is a long lived perenial and can grow to great lenghts.
To propagate the cutting, take pieces of new growth at least 8 inches long but not much longer, dip in a rooting hormone such as rootone and bury at least 1 inch deep in a soil less mix in a pot and encase the pot in a clear plastic bag.  Keep the interior humid but the soil should not be soggy.  Rooting should occur within 8 weeks.

I hope this helps.
Tom