I don't know an answer, but wanted to say mine pups like crazy. Pups have pups!LOL Maybe disturb the roots a little?....

You want fertilizer with a good bit of potassium (K). I use 20-0-30. You might try 15-0-15 or something like that but look for potassium of 4 or 5%. The rapid growth ( they do grow rapidly anyway ) could be due to the extra N. What fertilizer are you using?

Currently I'm using Dr. Earth all purpose (5-5-5) with a little ammonia added. I used to use miracle grow for everything years ago (great success with it) then I had a small nursery where I grew organic herb plants for sale so I moved to all organic soil and fertilizers. If I decide to sell plants / produce in the future I would like to keep everything organic - so now I am using Dr. Earth all purpose 5-5-5 and have added a little ammonia to some water for the banana plant. I'm now growing mostly tropicals / sub tropicals so I need to do some research to see what fertilizer will work best. Everything seems healthy and growing very well right now.

I'll add some potassium / reduce the nitrogen and try that. Thanks!

I fertilized it and put it outside. It's starting to send up pups now :)

I have two dwarf cavendish plants that are growing outside. They survived the terrible winter and have been coming back vigorously since March. If we have a milder (normal) winter they won't have to be cut back to the corm like I had to this year.

Where are you located?