It varies place to place. I ain't no pro, but when the water around the places I fish in NC gets around 60-63 degrees the fight is on. I've caught them spawning in cooler and warmer water, but depending on the over all depth of where you fishing and the water feeding it, you may get different results. Crappie are finiky, they may come in shallow then move back deeper, before they decide to spawn. That's my two cents, but I might change my mind tomorrow.
This only my opinion, but nothing you can say will change my mind. That makes it a FACT.
Today is a Blessed Day and a Prosperous Day