I've had to cut the vine back on mine three times in four years. Once they vine they rocket! Also, I found that once they vine they produce basals readily. Mine put out four basals the last time I cut it. I cut back two of them to keep it from weakening too much. Right now it's a small plant again. So just be patient, and you'll have some basals fairly soon most likely.
Very nice nep uphwiz!
Looks like you take great care of the plant and the pics are nice a vibrant.
I have had this for a few years and have cut it back once.
It readily produces basals for me. 5 since I have gotten it.
Here are some pics of mine from 2009 when it was just starting to vine. No basals on the plant when I posted these pics.
Here is the Nep now. It has vined again and has 2 basels that are starting to take off.
It looks a bit rough as I put it outside in full sun this summer and it burnt badly at first.
PICS taken today 8/31/12