Petiole too short

[Than]

Two of my ravenala have produced new leaves recently but they seem to have very short petioles and they're stuck near the stem. Could it be because of the sun during the day or the night cold? They spent the winter indoors. Temperatures now range from 58 to 73 F. I am attaching a photo. Any ideas what the problem might be?

 

 

[Merlyn]

It might be a combination of two things:

• If it was in shade before, and is now in sun...the old fronds could be "etoliated" and larger than normal.  The new ones may grow out smaller but more sun-acclimated.
• Low temps on my palms means slower growth rate, and the petioles are noticeably shorter when they open.  This is most obvious on my backyard Bismarck, where the petiole is several feet shorter than the summer-grown fronds.