Why is Amaryllis not blooming?

I have some amaryllis plants in the same pot. I started them from seeds several years ago. They were given in a seed swap back on Garden Talk, and the three seeds have all grown and made babies. None have bloomed yet, even though they are is over 5 years old. I was thinking that maybe the should be re-potted and divided? The website about growing them from seed says they usually bloom in three to five years. They are in a sunny south window. I no longer have that link. They are nice and healthy otherwise.

 

First of all are they Amaryllis ( outdoor plants that flower Aug to Oct ) or Hippeastrum ( indoor plants that flower from Dec to April / May ).