How big are they? Plants?/Pots? It sounds like they might be ready to transplant. A few is no big deal, but when they start you should check to see that others are not growing up the side of the pot. Thats when its time to transplant, IMO. . . Others may have more input. . .
And the pots? how big are they? These new babies for their first transplant? If they are seedlings and the roots have shown, I would transplant them into pots now. Especially since you don't want the roots to get ANY light. . .