I bought a spider plant a few years ago that went mad and it went mad, I put it in a pot about three times the diameter and it filled it really quickly. It has produced lots of babies which I then repot and do really well to a point, then just become very leggy and starts producing babies (which I cut off) They are are good sunlight, damp etc so I'm not sure where I'm going wrong? How can I encourage outward growth (to the edge of the pot) rather than top growth?