Banana Plant-Anybody know what can be the problem?

Make sure it is in a warm environment, especially the roots. Avoid frost.

The Super Dwarf grow only 3 to 4 feet tall, maybe you got a dwarf?

From your picture it looks like it is in the shade or partial shade. Banana plants are tropical plants and need plenty of sun. You should move them in the fall just before the first frost. According to where you live, you should dig them up before the first frost and put them in a warm dark place for the winter. My parents(who lived in Memphis, TN) dug their banana trees up every fall, palced them under their house and re-planted them every spring. Their plant grew to about 12' - 15' high and produced smart small bananas after a few years.

they don't like to be too wet, and they can get mites, but I don't know much else about them

First of all you need to place them in a sunny area, keep the blocks away from the plant and buy fertilizer to place around it. And last check the place were you got them to see if they have other suggestions.

we had a half acre of banana trees and the mother tree has her daughter

tree beside her. the mother tree has to be chopped down for the daughter tree

to thrive and bear fruit. kind of sad but true!

Looks like it may be root-bound. It should be repotted into a container that is at least 50% larger. When you transplant it, feed it either granular or liquid fertilizer to prevent transplant shock.

Hola carmen , yo creo que tus plantas estan en mucha sombra, pero se ven saludables. Yo tengo el mismo caso lo unico que las mias estan en pleno sol. El problema es la tierra que tiene mucha arena.

You still get Bananas and an easier tree to maintain