I disagree somewhat with jays response. a ball python will reach close to its full length within 3-4 years. but balls really never stop growing. the continue to grow their hole life. it is so slow and very spread out over the years after that, that you won't notice. by the time of its death(they can live over 30 years) it might have gained 3 more inches. if you want a large ball, then you can powerfeed.like jay said, it can do them harm. but only if do to much, to often.if you do it at the rite time, it can grow very fast. i had a male go from 2 3/4 to almost 4 feet in just three month of powerfeeding.goodluck if you try but be very careful. ask a worker at your local reptile store and they'll help you out.